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Chapter 37 • Vaginal Discharge and Itching
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439
examination is the frog leg position. Have the parent sit
on a chair and then have the patient sit on her parent’s
lap for the examination. The most common problem
(vulvovaginitis) of the younger child requires only the
lower third of the vagina to be visualized. A more detailed visual examination requires labial separation and
labial traction.
Perform an Internal Vaginal Examination
Note the condition of the vaginal walls. A plastic
speculum makes vaginal wall inspection easy and
helps in the identication of a foreign body for removal. In children, the knee-chest position is useful for
inspecting the vagina. If a foreign body is suspected in
children, removal is done using sedation. Pale or mottled red splotches of the vaginal mucosa with a sticky,
yellow-brown discharge are associated with atrophic
vaginitis. In severe cases of atrophic vaginitis, the pale,
thin mucosa may have adhered to the opposing vaginal
wall, and the speculum examination often causes an
oozing bloody discharge.
The appearance of the cervix should be noted.
A friable or “strawberry” appearance of cervical
petechiae with a frothy, foul-smelling discharge is
descriptive of a trichomonas infection. A mucopurulent discharge from the cervical os is an indication to
obtain an endocervical sample for gonorrhea and
chlamydia testing. This discharge is yellowish-green
when collected on an endocervical swab. The character of the discharge does not consistently identify
common infectious causes of vaginitis. Treat vaginal
infections before the Papanicolaou test is obtained
because BV and trichomoniasis may cause inammatory atypia results.
Obtain a sample for testing. The wet mount is a valuable diagnostic tool, and a sample of vaginal discharge
is best obtained from the lateral vaginal fornices. Three
positive characteristics for any one etiology can correctly identify the causative agent (e.g., increased pH;
the presence of “clue cells,” which are epithelial cells
full of bacteria that obscure the cell border; and a thin
gray discharge seen in BV) (see Differential Diagnosis). DNA testing and/or culture may also be indicated
(see Laboratory and Diagnostic Studies). Cultures for
BV, fungal infections, and T. vaginalis are not routinely
recommended and are usually reserved for determining
resistant organisms.
Perform a Bimanual Examination
Assess the condition of the uterus, fallopian tubes, and
ovaries by checking for uterine and cervical motion
tenderness (CMT), ovarian size, and presence of
masses. CMT or pain on palpation of the uterus and
adnexa conrms the spread of vaginitis or cervicitis
to the upper genital tract and results in PID. This
warrants immediate evaluation and treatment or referral to prevent tubal scarring, ectopic pregnancy, and
infertility.
Perform a Vaginal-Rectal Examination
Vaginal-rectal examination is an important technique
in assessing the posterior uterus and condition of the
cul-de-sac as well as the rectum. The internal examination glove must be changed before rectal insertion
to prevent contamination of the rectum with vaginal
discharge organisms. A rectal examination, using the
fth digit, is used to palpate a foreign body and to
check pelvic anatomy in the child.
LABORATORY AND DIAGNOSTIC STUDIES
Potassium Hydroxide and Wet Mount/Preparation
Obtain a discharge sample from the lateral fornices of
the vagina using a cotton-tipped applicator. There are
several acceptable techniques for preparing a diagnoses and wet mount. One is to prepare two slides with a
smear of vaginal discharge. To one slide, add a drop of
10% KOH and put a coverslip in place. To the other
slide, add a drop of normal saline and put a coverslip
in place. The whiff test is positive when the addition of
the 10% KOH produces a shy odor, which is caused
by the release of amines. The whiff test has a positive
predictive value of 76% for BV. Look under the microscope at the KOH slide for the presence of branching
and budding hyphae that are characteristic of yeast infection. Examine the saline wet mount microscopically
for motile trichomonads that signal the presence
of trichomonas. Clue cells are characteristic of BV (see
Figure 37-1).
Test for pH
Most litmus paper reads the pH range from 3.0 to 9.0.
This is a simple inexpensive test to aid in determining
the cause of the vaginal discharge. Normal vaginal secretions have a pH less than 4.5. A pH greater than 4.5
is consistent with BV, trichomoniasis, or atrophic
vaginitis.
Fungal Culture or Sabouraud Agar Culture
Fungal culture may be needed in the diagnosis of
non-Candida albicans (e.g., C. glabrata, C. tropicalis,
C. krusei) that are refractory to medication regimens.
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Chapter 37 • Vaginal Discharge and Itching
Herpes Viral Culture
Viral culture is the most specic method of diagnosing
herpes. Results may take from 1 to 7 days, with maximum sensitivity achieved at 5 to 7 days. The herpes
culture will probably not be able to identify the causative agent if the specimen is taken from a lesion that
is 5 or more days old. It is important to document
positive genital herpes infections in the pregnant
woman and in skin lesions of the newborn. Collect
cells or uid from a fresh sore with a cotton swab and
place them in the culture container. You may need to
unroof a vesicle to obtain a specimen.
Herpesvirus Antigen Detection Test
This test detects antigens on the surface of cells infected with the herpes virus. Cells from a fresh sore are
scraped off and then smeared onto a microscope slide.
This test may be done in addition to or in place of a
viral culture.
Tzanck Smear
Characteristic ndings of a Tzanck smear are multinucleated giant cells that are likely to be found if the
specimen is from an intact herpes lesion. Prepare the
Tzanck smear by removing the roof of the vesicle and
scraping the skin with a scalpel blade. Make sure that
the base and the margins of the vesicle are scraped.
Do not use the vesicular uid for this specimen. The
cellular material is spread onto a glass slide, xed
with absolute alcohol for 1 minute, and then stained
with Wright stain. Alternative staining methods are
available, and guidelines can be obtained from local
laboratories.
Modified Diamond Culture
Diamond culture is used to identify Trichomonas species,
but it is seldom needed to make the diagnosis.
Thayer-Martin Culture
Thayer-Martin medium is a bacterial culture that identies gonococcal infections. A culture is taken from the
endocervical canal of the uterine cervix. First remove
excess mucus from a portion of the cervix using a cotton ball held in ring forceps or a large cotton-tipped
procto-swab. Insert a sterile cotton-tipped applicator
(Q-tip) into the endocervical canal and allow it to absorb the mucus for 10 to 30 seconds before inoculating
the medium. Inoculate the medium bottle or plate in a
zigzag manner while simultaneously rolling the small
cotton-tipped applicator. When opening the ThayerMartin culture bottle, avoid holding the bottle totally
upright, which will allow for the loss of the carbon
dioxide from the specimen collection bottle.
DNA Testing for Infectious Organisms
DNA testing using a sample taken from the vagina
provides rapid, sensitive, and specic results. A number of products are available. DNA tests include DNA
probes, nucleic acid amplication tests (NAATs), and
polymerase chain reaction assays. Tests are available
for Chlamydia trachomatis, N. gonorrhoeae, T. vagi-
nalis, Gardnerella vaginalis, Candida species, and
herpes simplex virus. Samples for chlamydia and gonorrhea testing can be obtained by the practitioner or by
the patient. Urine NAATs can be used to screen for
possible STIs in children. A positive test result must be
followed up with a culture for denitive diagnosis.
Syphilis Testing
Serology tests are used for screening and diagnosing
syphilis and are recommended if other STIs are found or
suspected. The screening tests are nontreponemal and
include VDRL (Venereal Disease Research Laboratory),
RPR (rapid plasma reagin), and EIA (enzyme immunoassay) tests. Diagnostic tests are T. pallidum-specic
EVIDENCE-BASED PRACTICE
This study of women in the United Kingdom compared selfswabbing vulvovaginal samples for sexually transmitted infections (STIs) with clinician-obtained endocervical samples.
The authors found that in women with symptoms suggestive
of gonorrheal infection, the DNA assays—both clinician- and
self-collected—were equivalent and more sensitive than gonorrhea culture. For chlamydia, self-collected vulvovaginal
swabs were significantly more sensitive than clinically obtained endocervical swabs (97% vs 88%) and had equal
Copyrighted 2015. IMNG. 116311:0315BN
Self-swabbing for Sexually Transmitted Infections
specificity (99.9% vs 100%). In women with symptoms of
an STI, the sensitivity was 97% vs 88%; in those with no
symptoms, the sensitivity was 97% vs 89%. The authors
concluded that self-collected vulvovaginal swabs are the
sample of choice for both chlamydia and gonorrhea testing in
women, regardless of whether or not symptoms are present.
When a clinical examination is performed, either the clinician
or the patient can collect a vulvovaginal swab sample.
Chapter 37 • Vaginal Discharge and Itching
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441
and include FTA-ABS (uorescent treponemal antibody
absorption test) and TPPA (T. pallidum particle aggluti-
nation assay). Detection of T. pallidum can also be done
using polymerase chain reaction DNA testing.
Urinalysis
Urinalysis should be obtained if the patient has dysuria. However, external pain on urination may originate from urine on inamed vulvar tissue, eliminating
the need for urinalysis.
Microscopy and Skin Scraping
Viewing a skin scraping under the microscope is used
to assist with the differential diagnosis of scabies and
pubic lice (see Chapter 28).
Scotch Tape Test
Use this test when you suspect pinworms (Enterobius
vermicularis), which occur most commonly in chil-
dren. Instruct the adult to apply adhesive cellophane
tape to the child’s perianal region early in the morning
when the child awakens. The tape is then removed,
placed in a plastic bag, and brought in to the clinic.
Place it on a glass slide and examine under a microscope for the presence of eggs. Parents may also be
able to see the worms by shining a ashlight on the
external anus of the child at night. The female worm is
about 10 mm long (see Figure 37-2).
macular or papular border. The surface will appear verrucous. False-positive results can occur with candidiasis, psoriasis, lichen planus, and sebaceous glands.
Follicle-Stimulating Hormone
Follicle-stimulating hormone (FSH) levels that are
greater than 30 mU/mL are diagnostic of perimenopause, and levels of 40 mU/mL or higher represent
menopause. This test is particularly helpful in establishing the hypoestrogenic status of a young woman
who is experiencing premature menopause and atrophic vaginitis (see Evidence-Based Practice box).
DIFFERENTIAL DIAGNOSIS
Discharges
Physiological Discharge
Normal vaginal discharge, produced by the cervical
and vulvar glands, is mucoid, clear or white in color,
and has no foul odor. The amount varies from scant to
profuse, depending on the amount of estrogen stimulation to the tissues. On occasion, physiological discharge can lead to slight vulvar irritation and mild
itching secondary to wetness. The vaginal pH is less
than 4.5. Wet mount reveals up to 3 to 5 white blood
cells (WBCs)/high-power eld (HPF) and the presence
of epithelial cells and lactobacilli.
Acetic Acid Test (Acetowhite)
The acetic acid test is best used to detect subclinical
lesions caused by human papillomavirus when a genital wart has been identied, when there has been sexual
contact, or when the Pap test indicates dysplasia. The
application of 5% acetic acid (vinegar) to the cervix,
labia, or perianal area causes the lesion to turn white
(acetowhite). Saturate a gauze pad with vinegar and
place on the lesion for 5 to 10 minutes. After this soaking, the white wart will have a sharp circumscribed
EVIDENCE-BASED PRACTICE
According to this systematic review, approximately 33% of
patients with vaginal discharge will have bacterial vaginosis,
25% will have candidiasis, and 10% will have trichomoniasis. The lack of a perceived odor makes candidiasis more
likely (LR, 2.2), but the absence of the symptom is not conclusive. No symptoms reliably identify trichomoniasis. A thick
or “curdy” discharge is compatible with yeast, but does not
Data from Piscitelli JT, Simel DL: Update: Vaginitis. In Simel DL, Drummond R (eds.): The rational clinical examination: Evidence based clinical
, New York, 2009, McGraw Hill.
diagnosis
Bacterial Vaginosis
BV is the most common cause of vaginal discharge and
is considered a disturbance in normal vaginal ora. It
is often found after intercourse with a new partner or in
conjunction with other STIs. Fifty percent of women
are asymptomatic; infection is associated with increased preterm labor in pregnant women and patients
undergoing vaginal surgical procedures (increased
infection). Symptoms include a thin homogeneous
white, gray, green, or brownish discharge that has a
Clinical Diagnosis of Vaginitis
rule out additional infection. Microscopic evaluation is
required to identify clue cells (bacterial vaginosis), yeast
forms (vaginal candidiasis), or trichomonads (vaginal trichomoniasis). The authors concluded that diagnosis is best
established by measuring the pH of the discharge, performing
the whiff test, and using microscopic examination.
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Chapter 37 • Vaginal Discharge and Itching
foul odor; there can be pelvic tenderness or pain but no
CMT. The vaginal pH is greater than 4.5. Wet mount
shows clue cells and a few lactobacilli; the “whiff” test
is positive (see Figure 37-1).
Candida Vulvovaginitis
Ninety percent of women with candida vulvovaginitis
present with vulvar pruritus. In children, it may be accompanied by oral thrush. The discharge is often thick,
white, and “curdy;” the labia are erythematous and
edematous. Vaginal pH is 4.0 to 4.7. A KOH wet mount
shows pseudohyphae and spores (see Figure 37-1).
Trichomoniasis
Trichomoniasis is asymptomatic in about half of the
women and 90% of the men affected. It is usually
transmitted via sexual contact but can also be spread
by fomites. Women with chronic infections will have
copious amounts of discharge and little or no inammation of the vaginal tissues. When there is an acute
infection, they will report vulvar itching, swelling,
and redness. The pH is greater than 5; the discharge is
white, grayish-green, or yellow, and sometimes
frothy; infrequently there will be a “strawberry cervix” (cervical petechiae). If the woman has douched
within the past 24 hours, the sensitivity of tests will
be greatly decreased. Wet mount shows “gyrating”
motile protozoa and often greater than 10 WBCs/HPF
(see Figure 37-1).
Atrophic Vaginitis
In atrophic vaginitis, there is a dry (shiny), pale, thin
vaginal wall caused by an insufcient amount of
endogenous estrogen. During menopause, the vaginal
mucosa and vulva, which lack glycogen, become fragile and are susceptible to injury and infection. Patients
may experience burning, dryness, irritation, or dyspareunia. This also occurs in postpartum women, those
who are breastfeeding, and prepubertal girls. The pH is
alkaline and ranges from 6.5 to 7.0. Wet mount shows
a few WBCs and is negative for pathogens.
Allergic Vaginitis
The causes of allergic vaginitis are different in children
and adults. In the child, the most common offending
agents are bubble baths and perfumed soaps. Adult
vulvovaginitis involves any harsh or caustic substance
that has direct contact with the area. Often a new brand
of vaginal lubricant, douche, spermicide, or condom
will cause the inammation and edema. Vinegar
douches stronger than 1 to 2 tablespoons per quart
of water may also irritate tissues. The wet mount is
positive for WBCs and negative for pseudohyphae.
Foreign Body
The presenting symptom in foreign body retention is a
very malodorous, whitish discharge. In children, the foreign body is as variable as those objects found in the ears
and nose. However, children younger than 12 months do
not have the coordination to insert anything into their vagina, so suspect child abuse in such cases and inspect for
bruising or excoriations. Wet mount reveals many WBCs.
Chlamydia
Chlamydia is the most prevalent STI in the United
States. About 30% of infected women are asymptomatic. Gonorrhea and chlamydia coexist in up to 60% of
patients. Women with chlamydia have an increasing
amount of vaginal discharge and bleeding after intercourse. Those at greatest risk for infection are younger
than 25 years, sexually active with three or more partners, and not using barrier methods of contraception.
Wet mount shows greater than 10 WBCs/HPF and few
microscopic bacteria. DNA testing conrms the diagnosis. Except for perinatal syndromes, nonsexual
transmission has not been reported; therefore, suspect
child abuse in children with chlamydia infection.
Gonorrhea
Gonorrhea is one of the most common reportable
diseases. Women are asymptomatic 50% to 80% of
the time. However, the patient may have purulent
discharge that originates from the endocervical columnar and transitional cells. Patients often experience inammation of Skene glands, Bartholin glands,
or the urethra, which causes pain and dysuria. Culture
or DNA testing conrms the diagnosis. A nding of
gonorrhea in children is considered specic evidence
of sexual abuse.
Pelvic Inflammatory Disease
PID is most commonly caused by Chlamydia trachomatis and N. gonorrhoeae (see Chapter 3) and can
produce bleeding, abdominal pain, fever, and vaginal
discharge. Women with PID have an increasing amount
of vaginal discharge and bleeding after intercourse.
Infection begins intravaginally in most cases and then
spreads upward, causing salpingitis. In the early stages,
women may be asymptomatic. Patients may have a
purulent discharge that originates from the endocervical columnar and transitional cells. With gonorrhea,
patients often experience inammation of Skene
Chapter 37 • Vaginal Discharge and Itching
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443
glands, Bartholin glands, or the urethra, which causes
pain and dysuria. On examination, abdominal tenderness, CMT, and adnexal tenderness are present. As
with peritonitis, patients may also have guarding and
rebound tenderness. WBCs and erythrocyte sedimentation rate are usually elevated. Cultures, Gram staining,
and DNA testing can assist with diagnosis. Women
with suspected PID should have a pregnancy test to
rule out ectopic pregnancy and complications of an
intrauterine pregnancy. All patients diagnosed with
acute PID should also be tested for HIV infection.
Itching and Lesions
Syphilis
The chancre of primary syphilis is an ulcerative lesion
that most often develops at the site of initial inoculation. The syphilitic chancre begins as a papule and
progresses to a painless, tender, hard, indurated ulcer.
The infection causes inguinal lymphadenopathy. Even
without treatment, the lesion will heal in 3 to 6 weeks.
Many chancres go unnoticed until the appearance of
condylomata lata, the warty papule of secondary syphilis, or a maculopapular rash on the palms of the hands
and soles of the feet. Diagnosis is conrmed with serological or DNA testing for syphilis.
Genital Warts
Genital warts (condylomata acuminata) are caused by the
human papillomavirus and may be precursors to genital
cancers. The warts may involve the vagina, cervix,
perineum, or perianal areas. Condylomata can be at or
raised verrucous lesions (Figure 37-3). The patient usu-
ally notices a bump in the genital region accompanied by
itching and leukorrhea. A wet mount should be performed
to rule out any coexisting vaginal infections. An acetic
acid test is helpful in identifying at warts. Referral to a
dermatologist or gynecologist is indicated for treatment of
warts of the urethra or anus. High-risk human papillomavirus testing of genital warts is not recommended.
FIGURE 37-3 Condylomata acuminata. (From Morse SA, Holmes
KK, Ballard R: Atlas of sexually transmitted diseases and AIDS,
ed. 3, St Louis, 2003, Mosby.)
FIGURE 37-4 Herpes. (Left from Habif. TP: Clinical dermatology, ed 4, St. Louis, 2004, Mosby. Right from
Morse SA, Holmes KK, Ballard R: Atlas of sexually transmitted diseases and AIDS, ed. 3, St Louis, 2003,
Mosby.)
Herpes
Herpetic lesions can be difcult to distinguish from
ulcerative lesions. The most typical presentation is
that of grouped vesicles on an erythematous base
that rupture and erode (Figure 37-4). A prodrome of
BA
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Chapter 37 • Vaginal Discharge and Itching
tingling or itching occurs before the outbreak of
the vesicles. On the vulva, the erosions are covered
with a whitish, exudative layer. Herpetic outbreaks
can involve the cervix, vagina, vulva, anus, or extragenital organs, like the pharynx. Culture, antigen
test, Tzanck smear, or DNA testing conrms the
diagnosis.
If the mother has an active primary herpes simplex
virus infection at the time of birth, the infant has a
50% risk of becoming infected. Recurrent maternal
infections impart a less than 5% risk of transmission.
Clinical signs of the infant’s infection become apparent in the rst week of life and pose the possibility
of death.
Molluscum Contagiosum
Molluscum are small (2 to 5 mm in diameter), umbilicated, esh-tone papules (Figure 37-5). These characteristic lesions are the hallmark of the diagnosis.
Scratching can spread them. Molluscum is an STI of
adults and a likely nding in HIV-infected patients.
When children are found to have genital molluscum,
suspect child abuse.
FIGURE 37-5 Molluscum contagiosum. (From Black M,
Ambros-Rudolph C, Edwards L, et al: Obstetric and gynecologic
dermatology, London, 2008, Mosby.)
DIFFERENTIAL DIAGNOSIS OF
Common Causes of Vaginal Discharge and Itching
CONDITION HISTORY PHYSICAL FINDINGS DIAGNOSTIC STUDIES
DISCHARGES
Physiological
discharge
Bacterial vaginosis Foul-smelling discharge Homogeneous thin white or
Candida vulvovaginitis
Trichomoniasis Watery discharge; foul odor Profuse, frothy, greenish
Atrophic vaginitis Dyspareunia; vaginal dryness Pale, thin vaginal mucosa;
Allergic vaginitis Examples: New bubble bath,
Foreign body Red and swollen vulva; vaginal
Chlamydia
Increase in discharge; no foul
odor, itching, or edema
Pruritic discharge White, curdy discharge;
soap, douche
discharge; history of tampon,
condom, or diaphragm use
Partner with nongonococcal
urethritis; asymptomatic;
discharge or bleeding
after intercourse
Clear or mucoid; pH ,4.5
gray discharge; pH .4.5
pH 4.0-5.0
discharge; red friable
cervix; pH 5.0-6.0
pH .4.5
Foul smell, erythema, “lost
tampon,” pH ,4.5
Bloody, foul-smelling
discharge
May or may not have
purulent discharge
Up to 3-5 WBCs/HPF;
epithelial cells, lactobacilli
Presence of KOH “whiff”
test; presence of clue
cells; few lactobacilli
(see Figure 37-1)
KOH prep: mycelia, budding,
branching yeast, pseudohyphae (see Figure 37-1)
Round or pear-shaped
protozoa; motile “gyrating”
flagella (see Figure 37-1)
Folded, clumped epithelial
cells
WBCs
WBCs
DNA testing; .10 WBCs/HPF
Chapter 37 • Vaginal Discharge and Itching
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445
DIFFERENTIAL DIAGNOSIS OF
Common Causes of Vaginal Discharge and Itching—cont’d
CONDITION HISTORY PHYSICAL FINDINGS DIAGNOSTIC STUDIES
DISCHARGES
Gonorrhea
Pelvic inflammatory
disease (PID)
ITCHING AND LESIONS
Syphilis
Genital warts Mild-to-moderate itching, foul
Herpes History of prodromal
Molluscum
contagiosum
CMT, Cervical motion tenderness; ESR, erythrocyte sedimentation rate; HIV, human immunodeficiency virus; HPF, high-power field; KOH, potassium
hydroxide; STI, sexually transmitted infection; WBC, white blood cell.
—cont’d
Partner with STI;
often asymptomatic
Bleeding, abdominal pain,
fever, and vaginal discharge; increasing amount
of vaginal discharge and
bleeding after intercourse
History of painless ulcerative
lesion; rash on palms and
soles of feet; warty growth
on vagina or anus
vaginal discharge; child:
history of sexual abuse;
adult: new or multiple
partners; history of warts
syndrome, paresthesias,
burning, itching; may
have mucoid vaginal
discharge
History of contact with
infected person;
if inflamed: itching
Purulent discharge;
inflammation of S kene/
Bartholin glands
CMT and adnexal tenderness;
may also have guarding
and rebound tenderness
Chancre: usually one but can
be more, painless ulceration; condylomata lata:
flat, whitish papule or
plaque; maculopapular
rash: palm, soles, body
Moist, pale-pink, verrucous
projections on base; located on vulva, vagina,
cervix, or perianal area
Grouped vesicles on red
base, erode to an ulcer;
if on mucous membrane,
exudates form; if on skin,
crusts form; redness,
edema, tender inguinal
lymph nodes
Flesh-colored, dome-shaped
papules, some with umbilication; usually 2-5 mm in
diameter
Gram stain; culture;
DNA testing
WBC; culture; Gram stain;
DNA testing (chlamydia
and gonococcus), syphilis
testing; ESR, C-reactive
protein; pregnancy, HIV
Syphilis and DNA testing
Acetic acid test: white
Viral culture; Tzanck smear;
DNA testing
None
References and Readings
Anderson MR, Klink K, Cohrssen A: Evaluation of vaginal com-
plaints, JAMA 291:1368, 2004.
Baron EJ, Miller JM, Weinstein MP, et al: A guide to utilization of
the microbiology laboratory for diagnosis of infectious diseases:
2013 recommendations by the Infectious Diseases Society of
America (IDSA) and the American Society for Microbiology
(ASM), Clin Infect Dis 57:e22, 2013.
Comkornruecha M: Gonococcal infections, Pediatr Rev 34:228, 2013.
Eckert LO: Clinical practice: Acute vulvovaginitis, N Engl J Med
355:1244, 2006.
French L, Horton J, Matousek M: Abnormal vaginal discharge: Using
ofce diagnostic testing more effectively, J Fam Pract 53:805, 2004.
Gradison M: Pelvic inammatory disease, Am Fam Physician
85:791, 2012.
Hainer BL, Gibson MV: Vaginitis, Am Fam Physician 83:807, 2011.
Jasper J: Vulvovaginitis in the prepubertal child, Clin Pediatr Emerg
Med 10:10, 2009.
Markle W, Conti T, Kad M: Sexuality transmitted diseases, Prim
Care 40:557, 2013.
Mitchell H: ABC of sexually transmitted infections: Vaginal
discharge—causes, diagnosis, and treatment, BMJ 328:1306,
2004.
Page C, Mounsey A, Rowland K: PURLs: Is self-swabbing for STIs
a good idea? J Fam Pract 62:651, 2013.
Piscitelli JT, Simel DL: Update: Vaginitis. In Simel DL, Drummond
R (eds.): The rational clinical examination: Evidence based clini-
cal diagnosis, New York, 2009, McGraw Hill.
Quan M: Vaginitis: Diagnosis and management, Postgrad Med
122:117, 2010.
Trent M: Pelvic inammatory disease, Pediatr Rev 34:163, 2013.
CHAPTER
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38
ision loss is a condition that ranges from vision
V
impairment to total blindness. For vision to occur, light is transmitted through the eye to photoreceptors in the retina that collect light and send neural
impulses to the brain. These impulses are then
processed to give information on what is being seen.
Vision loss occurs with any interruption in this visual
pathway, such as opacication of the cornea, lens, or
vitreous body (see Chapter 30, Figure 30-1 for the
anatomical structures of the eye). Vision loss also
occurs when light energy cannot be converted into
neural impulses, such as in glaucoma, retinal detachment, ischemic optic nerve atrophy, and pituitary
or occipital tumors. Because vision loss is a selfreported condition, functional causes, formerly called
malingering or hysteria, can be considered.
The most common causes of vision loss in adults
are refractive errors, cataracts, glaucoma, age-related
macular degeneration (AMD), and diabetic retinopathy. In all cases, impaired vision requires evaluation
by an ophthalmologist. However, knowledge of the
causes of vision loss can provide important clues to
the diagnosis of these conditions.
Vision Loss
Blurring of Vision
Distinguish between loss of vision and loss of visual
acuity. Vision loss is the absence of vision, completely
or partially, in one or both eyes. Blurriness refers to a
change in the acuity of vision. The most common
cause of visual acuity change is refractive error.
Ability to Focus
Patients who are without sight have no ocular alignment and commonly manifest a gross searching and
wandering nystagmus. Nystagmus in the rst year of
life suggests bilateral vision loss until proved otherwise. In infancy, vision loss is a common cause of
nystagmus.
Visual Fixation
Even though the visual system is incompletely developed at birth, most infants can see and will demonstrate visual interest when stimulated by a human
face. At birth the infant will have visual xation
present, and by 2 months of age xation will be well
developed. Any parental concern about a child’s
visual functioning is an important history nding.
DIAGNOSTIC REASONING: FOCUSED
HISTORY
What is the extent of vision loss?
Key Questions
l
What can you see? Can you detect light?
l
Is your vision blurred?
l
To self: Does the patient look at me?
l
If a child: Does the child’s eye wander?
Total Absence of Vision
Disease that affects the optic nerve or retina, such as
retinal detachment, leads to total loss of vision.
Blindness is a complete lack of form and visual light
perception.
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Is this an emergency that requires immediate
intervention?
Key Questions
l
Was the loss of vision sudden?
l
Is the loss in one or both eyes?
l
Is the loss complete or partial?
l
Is there any pain with the loss of vision?
l
Are there other symptoms associated with the loss,
such as a ash of light?
l
Was the loss momentary or persistent?
Onset
Sudden loss of vision suggests a vascular etiology, specically occlusion of the central retinal artery until proven
otherwise. In occlusion of the central retinal artery, the
Chapter 38 • Vision Loss
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patient notes that vision is lost suddenly, and light cannot
be distinguished from dark. Loss of vision in one eye in-
dicates that the problem is anterior to the chiasm; hemi-
anopic eld defects in both eyes suggest a postchiasmal
lesion (Figure 38-1). Occlusion of the central retinal ar-
tery is an emergency and requires immediate treatment.
Pain
Sudden loss of vision with eye pain and photophobia
indicates pathology of the cornea, iris, and ciliary
body. Sudden loss of vision with a red painful eye may
indicate acute-angle glaucoma (see Chapter 30).
Inammation, demyelinization, or degeneration of the
optic nerve causes pain on movement of the eye and is
thought to be the result of general inammation of
the posterior portion of the orbit or inammation of the
optic nerve (cranial nerve II). Retrobulbar neuritis is
the most common disease in this category.
A common cause of sudden loss of vision without
pain is vitreous hemorrhage. The patient describes oaters that begin to drift in front of the eye, followed by a
red glow. The vision gradually fades until only light and
LEFT RIGHT
dark are distinguished. Painless vision loss is also associated with macular degeneration, retinal detachment, diabetic retinopathy, and anterior ischemic optic neuropathy.
Children
In children, acute optic neuritis rarely occurs as an
isolated condition and is usually a manifestation of a
neurological or systemic disease such as meningitis, viral
infection, or demyelinizing diseases. It may also be associated with lead poisoning and long-term use of certain
drugs, most notably chloramphenicol or vincristine.
Flash of Light With Loss of Vision
Patients who have retinal detachment describe a ash
of light shortly before loss of vision. Some patients
describe a veil over the eye either just before or
immediately after the ash. The reason for the ashes
is that detachment of the retina causes mechanical
stimulation of the rods and cones as it tears away from
the pigment epithelium and oats free.
Patients whose retinae pull away or tear but do not
detach experience the same ash of light as those with
SCOTOMATA
LEFT RIGHT
1
Blind eye
Optic nerve
Optic chiasm
Optic tract
Lower occipital cortex
Upper occipital cortex
FIGURE 38-1 Visual fields and five locations of visual field defects and associated visual field changes.
Examples of visual field defects along the optic nerve, optic chiasm, optic tracts, and optic radiations in the
cortex. (From Ferri FF: Ferri’s color atlas and text of clinical medicine, Philadelphia, 2008, Saunders.)
1
2
3
5
Upper occipital radiation
4
Lower occipital radiation
2
Bitemporal hemianopsia
3
Left homonymous
hemianopsia
4
Left upper homonymous
quadrantanopsia
5
Left lower homonymous
quadrantanopsia
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Chapter 38 • Vision Loss
retinal detachment. They may also experience momentary total or partial loss of vision in the affected eye.
Transient Loss of Vision
Some patients with migraine headaches experience a
scotoma, or an area of impaired vision within the visual
eld, before the onset of the headache. The scotoma may
be either positive (the patient sees a light spot or scintillating ashes [scintillating scotoma]) or negative (the patient
experiences a blind spot). Scotoma may be prodromal to
a migraine headache. Profound anxiety can produce a
transient loss of vision or a perceived loss of vision.
Can I rule out trauma?
Key Questions
l
Is there a history of head trauma?
l
Is there a history of eye trauma?
l
Has there been a chemical or thermal injury?
Head Trauma
Loss of vision is most likely to occur after trauma to the
occiput. The vision loss is sudden and complete, but
vision usually returns in a matter of hours. Severe head
trauma with skull fracture but without direct damage
to the eyeball can result in loss of vision that occurs
immediately or shortly thereafter. Occasionally a patient
can have good vision in the affected eye after the accident and subsequently lose vision as a result of severe
retrobulbar hemorrhage. In children, trauma is the most
common cause of retinal detachment. Abusive head
trauma, called shaken baby syndrome, may result in
retinal and vitreous hemorrhage.
Eye Trauma
Blunt trauma occurs when an object impacts the bony
orbit of the eye. High-velocity injuries to the eye are
not always immediately obvious. Small perforations
or penetrations of the cornea may appear similar to
corneal abrasions. Sharp trauma includes impact from
a sharp object that may perforate the cornea, leaking
uid from the eye.
Cataract formation is a result of major trauma to the
eye in children. Opacication of the lens can result
from a blunt or penetrating injury.
Chemical or Thermal Trauma
Alkaline burns from household cleaners and lawn
and garden products can cause irreversible vision loss.
Exposure to extreme heat or ames can damage the
cornea and eyelids.
Minutes make a difference with chemical trauma to
the eye; treat rst and examine later. Wash the eye with
copious amounts of water or normal saline solution
immediately for an alkaline burn.
Is the vision loss because of a chronic problem?
Key Questions
l
How long has vision loss been present?
l
Has vision decreased over time?
Progression of Vision Loss
Slowly progressive degenerative disease of any part of
the eye can cause progressive vision loss. Progressive
loss of visual acuity and color vision can be seen with
optic gliomas, the most frequently occurring tumor of the
optic nerve in childhood. A history of neurobromatosis
can be found in 25% of patients. Children who have
surgery for cataracts are especially at risk for glaucoma.
Glaucoma may cause chronic loss of vision. AMD is associated with decreased reading vision (see Chapter 30).
Is this related to a genetic, familial, or intrauterine risk?
Key Questions
l
Is there a family history of vision or eye problems?
l
Is there a history of maternal, intrapartum, or neonatal
conditions?
Family History
A family history of retinoblastoma, congenital cataracts, or metabolic or genetic disease is a risk factor for
visual and ocular abnormalities. Retinoblastoma occurs
in 12% of children with a family history. Hereditary
congenital cataracts occur in 10% to 25% of children
with a family history. Autosomal dominant inheritance
is the most common cause.
Maternal, Intrapartum, and Neonatal Risks
Infants at risk for vision problems are those who are
premature, have been on oxygen therapy, are low birth
weight, or have mothers who have had infections
related to human immunodeciency virus/acquired
immune deciency syndrome or to toxoplasmosis,
rubella, cytomegalovirus, or herpes simplex—known
as the TORCH complex of infections. These conditions
during pregnancy may produce blindness at birth or
vision loss later in life. Down syndrome is associated
with cataracts. Children with galactosemia develop
cataracts in infancy. Children with galactokinase
deciency develop cataracts in the rst decade of life.
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