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Chapter 24 • Penile Discharge 301
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symptomatic 2 to 6 days after exposure and produces
the classic yellow-green profuse spontaneous drainage.
On examination, the penis will be normal in appearance except for the copious discharge. Diagnosis is
established by DNA testing and is conrmed by Gram
stain and urethral culture.
Nongonococcal Urethritis
NGU can produce penile discharge, although on examination, discharge may not be present. NGU typically develops over a longer incubation period of 8 to
21 days, and 75% of patients present with a clear or
mucoid discharge.
Chlamydia is the most common nongonococcal causative organism. The resulting urethritis is characterized
by a scant mucoid discharge visible before the rst urination of the day. The patient may complain of irritation
around the meatus of the urethra or have vague symptoms. On examination, stripping the penis may produce
scant mucoid discharge. DNA testing is used to diagnose
Chlamydia, and Gram stains are used to rule out and
establish nongonococcal disease, of which chlamydial
infection is the most frequent. Urine screening tests can
be used to identify DNA chlamydial particles.
Prostatitis
Patients with acute bacterial prostatitis are likely to
look and feel sick and be febrile. They usually complain of dysuria, burning, frequency, and nocturia (see
Chapter 17). Prostatic massage is contraindicated in
acute bacterial prostatitis.
Patients with chronic prostatitis do not present
as acutely ill but have a history of prostate problems.
A causative organism may not be identied (see
Chapter 17).
Epididymitis and Orchitis
The patient with epididymitis/orchitis is usually a
sexually active young male, and pain is likely the presenting symptom. The patient may also have a urethral
discharge. The patient may be febrile. The history usually indicates a slower onset of discomfort over hours
or days compared to torsion testicle, which has a rapid
onset of symptoms. Elevation of the affected testicle
may reduce the discomfort. Swelling of the scrotum
and testicle may be present. Doppler ow studies with
color can locate hot spots and identify intact blood
ow (see Chapter 17).
Complicated Urethritis
The examiner should recognize common complications of urethritis. Periurethritis may progress to urethral stricture in untreated cases, causing banding of
the penile urethra in the shaft of the penis. Prostatitis
can develop and progress to a systemic inammatory
response, causing chills and fever. Extension of inammation to other structures of the urinary tract may result in acute infection of the epididymis and testicles.
Orchitis, a testicular inammation, presents with a
swollen and tender testicle. Disseminated systemic
urethral infection produces small tender papules or
petechiae on the skin surfaces of the hands, arms, and
legs. They may further develop into pustules and
become hemorrhagic or necrotic. Joints can become
involved with tenosynovitis and arthritis with synovial
effusion in Reiter syndrome. Monarticular joint or
tendon involvement should be investigated further.
Reiter Syndrome
As a complication of a urethral infection, Reiter syndrome commonly includes joint or tendon involvement, but conjunctivitis and skin lesions may also be
present. History includes a urethral infection within 1
to 3 weeks. HLA-B27 antigen typing may support
conrmation of the diagnosis.
Balanitis
Balanitis is inammation of the glans penis. Balanitis involving the foreskin or prepuce is called balanoposthitis. Uncircumcised men with poor personal
hygiene are most affected by balanitis. Lack of aeration and irritation because of smegma and discharge
surrounding the glans penis cause inammation and
edema. The most common complication of balanitis
is phimosis, or inability to retract the foreskin from
the glans penis.
302 Chapter 24 • Penile Discharge
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DIFFERENTIAL DIAGNOSIS OF Common Causes of Penile Discharge
CONDITION HISTORY PHYSICAL FINDINGS DIAGNOSTIC STUDIES
Balanitis Not circumcised; poor hygiene
practices
Urethritis
Gonococcal
urethritis
Nongonococcal
urethritis
Complicated Urethritis
Acute bacterial
prostatitis
Epididymitis/
orchitis
Reiter syndrome Joint and tendon involvement;
NAAT, nucleic acid amplification test.
Unprotected sexual activity;
abrupt onset of symptoms
3-5 days after exposure;
yellow-green discharge;
classic symptoms reported
by males: frequency, urgency,
dysuria; dysuria may be worse
at beginning of urine flow
Unprotected sexual
activity; longer incubation
period (8-21 days); meatal
itching or irritation; scant
mucoidlike discharge, if
present, before first voiding
of day; symptoms vary and
range in severity for urgency,
frequency, and dysuria
Chills, fever; 30-50 yr of age;
onset of symptoms over days;
pain in rectal, perianal area,
low back, and abdomen
Abrupt onset over several hours;
febrile, pain in scrotum and/or
testicles
urethritis
Localized erythema and ede-
ma; presence of smegma
Yellow-green discharge;
spontaneous or copious
amounts with stripping of
penis
Thin mucoid discharge may
be absent or minimal with
penile milking or stripping
May have fever; painful pros-
tate; do not massage
Tender, swollen epididymis
and/or testicles; elevation of
affected testicle may lessen
discomfort; may have fever
Joint and tendon involve-
ment, decreased range of
motion; skin and mucous
lesions; conjunctivitis
None; history and physical
examination
Collect specimens at least
1 hr, preferably 4 hr, after
last voiding; Gram stain,
culture; urine DNA testing
for gonococcus (NAATs)
Gram stain; culture; urine
DNA testing for
Chlamydia (NAATs)
Segmental urine
specimens; culture and
sensitivity
Doppler flow studies with
color
Blood, synovial fluid, HLA-
B27 antigen; radiographs
REFERENCES AND READINGS
Barth WF, Segal K: Reactive arthritis (Reiter’s Syndrome), Am Fam
Physician 60:499, 1999.
Blaivas M, Brannam L: Testicular ultrasound, Emerg Med Clin
North Am 22:723, 2004.
Blake D: The future is here: noninvasive diagnosis of STDs, Contemp
Pediatr 2:71, 2001.
Bremnor JD, Sadovsky R: Evaluation of dysuria in adults, Am Fam
Physician 65:1589, 2002.
Brill J: Diagnosis and treatment of urethritis in men, Am Fam Phys
81:873, 2010.
Centers for Disease Control and Prevention: Sexually transmitted
diseases treatment guidelines 2006, MMWR 55:1, 2006. [published
errata appeared in MMWR, 55:997, 2006.].
Diaz-Parker C, Bratslavsky G: Male genitourinary disease: urethritis,
epididymitis, and prostatitis, Clin Rev 15:40, 2005.
Luzzi GA, O’Brien TS: Acute epididymitis, BJU Int 87:747, 2001.
Miller KE: Diagnosis and treatment of Neisseria gonorrhoeae
infections, Am Fam Physician 73:1779, 2006.
Parker CT, Thomas D: Reiter’s syndrome and reactive arthritis, J Am
Osteopath Assoc 100:101, 2000.
Richens J: Main presentations of sexually transmitted infections in
men, BMJ 328:1251, 2004.
Simpson T, Oh MK: Urethritis and cervicitis in adolescents, Adolesc
Med Clin 15:253, 2004.
Wren T: Penile and testicular disorders, Nurs Clin North Am 39:319,
2004.
C H A P T E R
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25
Rashes and Skin Lesions
ermatological problems result from a number
of mechanisms, including inammatory, in-
D
(traumatic and exposure-induced). At times, the
mechanism may be readily identied, such as the infectious bacterial etiology in impetigo. However,
some dermatological lesions may be classied in
more than one way. Most insect bites, for example,
involve both environmental (the bite) and inammatory (the response) mechanisms. Awareness of the
potential mechanism of any skin rash or lesion is
most helpful in identifying the risk a person may have
for other illnesses. For example, persons with eczema
are also frequently at risk for or have other atopic
conditions, notably asthma and/or allergies. Thousands of skin disorders have been described, but only
a small number accounts for the vast majority of
patient visits.
on a carefully focused history and physical examination. The provider needs to be familiar with the
characteristics of various skin lesions; anatomy,
physiology, and pathophysiology of the skin; clinical appearance of the basic lesion; arrangement and
distribution of the lesion; and clinicopathological
correlations. Common symptoms associated with
specific lesions, such as itching or fever, are also
important to know. It is necessary to quickly identify life-threatening diseases and those that are
highly contagious. Ultimately, competence in dermatological assessment involves recognition through
repetition.
fectious, immunological, and environmental
Evaluation of rashes and skin lesions depends
DIAGNOSTIC REASONING: INITIAL
FOCUSED PHYSICAL EXAMINATION
Initial Inspection
Dermatological assessment is similar to the assessment of
most other body systems in that it depends on patient history and physical assessment. However, sometimes a brief
physical assessment preceding the history can assist in the
development of the initial differential diagnosis, followed
by a focused history and further physical examination.
Morphological Criteria
Examination involves the classication of the lesion
based on a number of morphological features (examples
are listed in Tables 25-1 and 25-2 and Figures 25-1 and
25-2). Evaluation should be systematic. Generally, morphological features should be analyzed as follows:
n Identify the location of the lesion(s).
n Identify the distribution of the lesions as localized,
regional, or generalized.
n Identify whether the lesion is primary (appearing
initially) or secondary (resulting from change in a
primary lesion).
n Identify the shape of the lesion and any arrangement
if numerous lesions are present.
n Describe the margins (borders).
n Describe the pigmentation, including variations.
n Palpate to assess texture and consistency.
n Measure the size of an individual lesion or estimate
size if lesions are numerous or widespread.
Examination in a systematic manner, and in part
before obtaining the majority of the history, provides
greater relevance to the data. Gloves are not necessary
unless there are open, draining, or exudative lesions.
303
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Table 25-1
NATURE OF LESION DESCRIPTION EXAMPLES
Primary Lesions (develop initially in response to change in internal or external environment of skin)
Macule Discrete flat change in color of skin; usually
Patch Discrete flat lesion (large macule); usually
Papule Discrete palpable elevation of skin; ,1-cm
Nodule Discrete palpable elevation of skin; may evolve
Plaque Slightly raised lesion, typically with flat
Wheal Transient pink/red swelling of skin; often
Tumor Large papule or nodule; usually
Pustule Raised lesion ,0.5-cm diameter containing
Vesicle Raised lesion ,0.5-cm diameter containing
Bulla Vesicle .0.5-cm diameter Bullous pemphigoid, contact (irritant)
Cyst Semi-solid lesion; varies in size from several
Secondary Lesions (appear as result of changes in primary lesions)
Crust Dried exudate that may have been serous,
Scale Thin plates of desquamated stratum corneum
Excoriation Shallow hemorrhagic excavation; linear or
Lichenification Thickening of skin with exaggeration of skin
Erosion Partial break in epidermis Herpes simplex or zoster, pemphigus
Fissure Linear crack in epidermis Xerosis, angular cheilitis, severe eczema
Distribution of Lesions
Localized
Regional Lesions involve specific region of body Acne vulgaris (pilosebaceous gland
Generalized Lesions appear widely distributed or in
Morphological Criteria of Rashes and Skin Lesions
Freckle, lentigo, purpura
,1.5-cm diameter
Pityriasis rosea, melasma, lentigo
.1.5-cm diameter
diameter; origin may be epidermal, dermal,
or both
from papule; may involve any level of skin
from epidermis to subcutis
surface; .1-cm diameter; scaling frequently
present
displaying central clearing; various shapes
and sizes; usually pruritic and lasts ,24 hr
.1-cm diameter
yellow cloudy fluid (usually infected)
clear fluid
mm to several cm; may become infected
purulent, or hemorrhagic
that flake off rather easily
punctate; results from scratching
creases; hallmark of chronic eczematous
dermatitis
Lesion appears in one small area Impetigo, herpes simplex (e.g., labialis),
numerous areas simultaneously
Nevi, seborrheic keratosis,
dermatofibroma
Nevi, basal cell carcinoma,
keratoacanthoma
Psoriasis, mycosis fungoides
Urticaria
Basal cell carcinoma, squamous cell
carcinoma, malignant melanoma
Folliculitis, acne (closed comedones)
Herpes simplex, herpes zoster, contact
(irritant) dermatitis
dermatitis, blisters of second-degree
sunburn
Sebaceous cyst
Impetigo, herpes zoster (late phase)
Xerosis, ichthyosis, psoriasis
Contact (irritant) dermatitis
Chronic eczema
vulgaris
tinea corporis (“ringworm”)
distribution), psoriasis (extensor
surfaces and skinfolds)
Urticaria, disseminated drug eruptions
Chapter 25 • Rashes and Skin Lesions 305
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Table 25-1
NATURE OF LESION DESCRIPTION EXAMPLES
Shape/Arrangement
Round/discoid Coin or ring shaped (no central clearing) Nummular eczema
Oval Ovoid shape Pityriasis rosea
Annular Round, active margins with central clearing Tinea corporis, sarcoidosis
Zosteriform (dermatomal) Following nerve or segment of body Herpes zoster
Polycyclic Interlocking or coalesced circles (formed by
Linear In a line Contact dermatitis
Iris/target lesion Pink macules with purple central papules Erythema multiforme
Stellate Star shaped Meningococcal septicemia
Serpiginous Snakelike or wavy line track Cutanea larva migrans
Reticulate Netlike or lacy Polyarteritis nodosa, lichen planus
Morbilliform Confluent and salmon colored Rubeola
Border/Margin
Discrete Well demarcated or defined; able to draw a line
Indistinct Poorly defined; having borders that merge
Active Margin of lesion shows greater activity than
Irregular Nonsmooth or notched margin Malignant melanoma
Border raised above
center
Advancing Expanding at margins Cellulitis
Associated Changes Within Lesions
Central clearing Erythematous border surrounds lighter skin Tinea eruptions
Desquamation Peeling or sloughing of skin Rash of toxic shock syndrome
Keratotic Hypertrophic stratum corneum Calluses, warts
Punctation Central umbilication or dimpling Basal cell carcinoma
Telangiectasias Dilated blood vessels within lesion blanch
Pigmentation
Flesh Neurofibroma, some nevi
Pink Eczema, pityriasis rosea
Erythematous Tinea eruptions, psoriasis
Salmon Psoriasis
Tan-brown Most nevi, pityriasis versicolor
Black Malignant melanoma
Pearly Basal cell carcinoma
Purple Purpura, Kaposi sarcoma
Violaceous Erysipelas
Yellow Lipoma
White Lichen planus
Morphological Criteria of Rashes and Skin Lesions—cont’d
Psoriasis, urticaria
enlargement of annular lesions)
lesions of erythema infectiosum
Psoriasis
around it with confidence
Nummular eczema
into normal skin or outlying ill-defined
papules
Tinea species eruptions
center
Center of lesion depressed compared to edge Basal cell carcinoma
Basal cell carcinoma, actinic keratosis
completely; may be markers of systemic
disease
306 Chapter 25 • Rashes and Skin Lesions
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Table 25-2
LESION* CHARACTERISTICS EXAMPLES
Annular Ring shaped Ringworm
Arcuate Partial rings Syphilis
Bizarre Irregular or geographic pattern not
Circinate Circular
Confluent Lesions run together Childhood exanthems
Discoid Disc-shaped without central clearing Lupus erythematosus
Discrete
eczematoid
Generalized
grouped
Iris Circle within circle; bull’s-eye lesion Erythema multiforme (iris)
Descriptive Dermatological Terms
related to any underlying anatomic
structure
Lesions remain separate
Inflammation with tendency to
vesiculate and crust
Widespread
Lesions clustered together
Factitial dermatitis
Eczema
Herpes simplex
Keratotic Horny thickening Psoriasis
Linear In lines Poison ivy dermatitis
Multiform
papulosquamous
reticulated
Serpiginous Snakelike, creeping Cutaneous larva migrans
Telangiectatic Relatively permanent dilation of
Universal
zosteriform
*Examples of different configurations of skin lesions and their descriptions are contained within Table 25-1. (From Swartz MH: Textbook of physical
diagnosis: history and examination, ed 6, Philadelphia, 2009, Saunders.)
†Also known as dermatomal.
†
More than one type of shape or lesion
Papules or plaques associated with
scaling
Lacelike network
superficial blood vessels
Entire body involved
Linear arrangement along nerve
distribution
Erythema multiforme psoriasis
Oral lichen planus
Osler-Weber-Rendu disease
Alopecia universalis
Herpes zoster
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Macule Papule Plaque
Wheal
Bulla Cyst
Scale
Nodule
Pustule
Excoriation Fissure
Vesicle
Ulcer
0 1
FIGURE 25-1 Types of skin lesions. (From Seidel HM, Ball JW, Dains JE, Flynn J, Solomon B, Stewart
R: Mosby’s guide to physical examination, ed 7, St Louis, 2011, Elsevier.)
cm
Crust
2
3 4
Atrophy
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A
FIGURE 25-2 Typical distribution of papulosquamous eruptions in children. A, Atopic dermatitis:
usually located on cheeks, creases of elbows, and knees. B, Seborrheic dermatitis: usually located
on scalp, behind ears, in thigh creases, and in eyebrows. C, Scabies: usually located on axillae, webs
of fingers and toes, and intragluteal area. (From Berkowitz C: Pediatrics: a primary care approach,
ed 2, Philadelphia, 2000, Saunders.)
B
DIAGNOSTIC REASONING:
FOCUSED HISTORY
Is the rash associated with an immediate
life-threatening condition?
Key Questions
n Do you have a fever?
n Are you short of breath?
n Do you have difculty swallowing?
n Is the rash tender and does it involve mucous mem-
branes?
Fever
Fever is common in viral exanthems (rashes), and the
accompanying condition is usually not life-threatening.
However, fever, irritability, hypotension, and a macular
or petechial rash may indicate meningococcemia. Treatment needs to be immediate to be lifesaving.
Allergic Reaction
Urticarial allergic reactions may be associated with
angioedema (swelling) of the extremities, face, lips,
tongue, and/or airway; cough; wheezing; shortness of
C
breath; or heart palpitations. The sooner symptoms
occur after the exposure to the allergen, the more severe is the reaction. Treatment needs to be instituted
immediately.
Rash with Mucosal Involvement
Toxic epidermal necrolysis (Stevens-Johnson syndrome)
is a tender, morbilliform, erythematous rash accompanied by fever, conjunctivitis, oral ulcers, and diarrhea.
Immediate hospitalization is required to treat exfoliation
of large areas of skin. The condition is usually druginduced.
Is the rash acute or chronic (recurrent)?
Key Questions
n How long have you had this rash?
n Have you ever had a rash like this before?
Onset
The diagnosis of skin lesions is initially aided by
categorizing the lesion as acute versus chronic or
recurrent. Acute eruptions, such as urticaria or various fungal rashes (tinea), are classied as such
Chapter 25 • Rashes and Skin Lesions 309
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because they have a tendency to be self-limiting or to
not recur after effective treatment. Chronic rashes,
such as psoriasis or eczema, may persist or be recurrent with exacerbations and remissions. Box 25-1
shows common rashes categorized by duration.
Ascertain the duration of the eruption at presentation; however, the initial occurrence of a chronic
rash may present acutely. Conversely, an acute eruption not optimally treated may present as a chronic
problem.
Where is the rash in its evolution?
Key Questions
n What did this look like initially?
n Has the rash changed? If so, how?
n Has it spread? Where?
Initial Presentation
Most skin lesions evolve over time, although this varies
from minutes with urticaria to weeks or even months
with psoriasis or mycosis fungoides.
Change in Lesion
Determining whether there has been a change from the
initial appearance of a lesion provides diagnostic clues.
The eruption of pityriasis rosea classically begins with
a “herald patch,” a single, scaly, erythematous patch
usually on the trunk, followed within days by a regional
outbreak of numerous smaller erythematous patches,
thus providing a key diagnostic clue. The rash may look
like that of ringworm, but it appears too quickly to be
ringworm. Another example of evolutionary change is
the eruption of herpes simplex virus (HSV), which begins with small vesicles that later umbilicate, possibly
ooze, and eventually crust before healing. A rash may
appear in different ways, depending on the point at
which evaluation is sought.
Spread
The way in which a rash spreads is helpful in diagnosing the specic rash. There are three general ways in
which a rash can spread: centripetal, or moving to the
center; centrifugal, or moving away from the center;
and caudal, or moving down.
What does the presence of pruritus tell me?
Box 25-1
Acute Chronic
Allergic or contact dermatitis
Candida dermatitis (diaper
rash, intertrigo)
Erythema infectiosum (fifth
disease)
Erythema multiforme
Fixed drug eruptions
Folliculitis
Herpes simplex virus (HSV)*
Herpes zoster/varicella
zoster (HZ)
Impetigo
Infestations (scabies,
pediculosis)
Insect bites
Kawasaki disease
Pityriasis rosea
Septicemia (meningococcal)
Scarlet fever
Tinea (corporis, pedis,
versicolor)
Urticaria*
Viral exanthems (measles)
*Occasionally recurrent
Duration of Rash
Acne vulgaris
Bullous pemphigus
Eczema
Erythema nodosum
Kaposi sarcoma
Mycosis fungoides
Polyarteritis nodosa
Psoriasis
Rosacea
Seborrheic dermatitis
Systemic lupus
erythematosus
Key Question
n Does it itch?
Itching
All dermatoses can be classied into three groups: a
small group that always itches, those that never itch,
and an intermediate group in which itching is variable
(Box 25-2). Pruritus is often reported to be worse at
night; during the day, pruritus is less troublesome
because the patient is distracted by daily routines. It
is only at bedtime that the slightest sensation of pruritus becomes overwhelming; this is because the patient is focusing on trying to sleep. Once the patient
scratches the area, histamine is released from the
inammatory cells (especially mast cells), and this
causes more pruritus and an itch/scratch cycle is
established.
Swimmer’s itch occurs in areas unprotected
by a swimsuit. Sea bather’s itch occurs in areas
under the swimsuit. Nocturnal pruritus most typically occurs in scabies infestations. Itching in the
absence of rash may be an important clue to internal
disease.
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Box 25-2
Always Itch May Itch Never Itch
Atopic
dermatitis
Urticaria
Insect bites
Scabies
Pediculosis
Lichen planus
Chickenpox
Itching: Comparison
Psoriasis
Impetigo
Tinea
Pityriasis
rosea
Warts
Neurofibromatosis
Vitiligo
Nevi
What does associated pain tell me?
Key Questions
n Is it painful or sore?
n Does it burn?
Pain
Pain is a rare symptom. The classic painful rash is associated with herpes zoster (HZ), including postherpetic neuralgia, although severe psoriasis or eczema,
when associated with ssures and bleeding, may be
described as painful by some patients. Soreness is a
more common symptom and is associated with numerous rashes. Tender erythema may be associated with
toxic epidermal necrolysis.
Burning
Burning is infrequently reported. It is most notable preceding the rash in herpesvirus infections (e.g., HSV or HZ).
What do associated symptoms tell me?
Key Questions
n Do you have a fever? Sore throat? Headache?
n How are you feeling in general?
Fever, Sore Throat, and Headache
Fever is a common presenting complaint in infectious diseases accompanied by rash, such as HZ,
erythema infectiosum, scarlet fever, or Kawasaki
disease. Malaise, sore throat, nausea, or vomiting
can occur with mononucleosis.
General Health
In a patient with a maculopapular eruption, the two
most common causes are drug reaction and viral illness. Inquire about viral symptoms, such as fever,
malaise, and upper respiratory tract or gastrointestinal
symptoms.
Are there possible contacts or sources
of contagion?
Key Questions
n Does anyone with whom you live or have close
contact have something similar? If so, how long
have they had it?
n Have you traveled recently? Where?
n What do you do for a living? What are your hobbies
or leisure activities?
n Do you have any pets? Have you been around
animals?
Living Situation
Explore the patient’s living situation. The geographic
details of his or her daily activities may help provide
diagnostic clues, particularly for rashes caused by infectious or infestation mechanisms. Children, in particular,
may contract scabies, pediculosis (lice), or impetigo by
direct contact in school or daycare.
Travel
A patient may develop a rash weeks or months after travel
exposure. Diseases endemic to other parts of the world
may present with rash, such as erythema nodosum, which
is common in Southeast Asia, or leprosy, which is common in Africa, Southeast Asia, and South America. Both
eruptions may also occur secondary to tuberculosis.
Camping trips to wooded areas, especially in the upper
Midwestern United States, may result in a bite by a deer
tick, causing Lyme disease, the leading vector-borne infectious disease. The resultant skin eruption in Lyme disease is known as erythema chronicum migrans (ECM),
which begins 4 to 20 days after the bite of the tick; only a
third of patients remember being bitten. Rocky mountain
spotted fever (Rickettsia rickettsii) is transmitted by a tick
bite and is common in the south Atlantic region of the
U.S. Initial symptoms are nonspecic; later symptoms are
rash and fever, usually requiring hospitalization.
Other Exposures
Outdoor occupations or leisure activities may expose
persons to a variety of rashes and lesions, including insect bites and allergic or contact dermatitis from poison
ivy or chemical substances. People exposed to animal
skins contaminated with Bacillus anthracis can develop
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