Questions

1. What condition is Duchenne’s dystrophy?

2. What causes the Duchenne’s dystrophy?

3. Who may carry a mutated gene? Who may inherit it?

4. What is dystrophin? What produces it?

5. How does the mutated gene act on the dystrophin production?

6. At what age do the first signs of the disease appear?

7. What symptoms are characteristic of Duchenne’s dystrophy in early childhood?

8. What muscles are mostly affected?

9. Why is the calf muscle prominent in Duchenne’s dystrophy?

10. What causes the spinal curvature?

11. Why can respiratory diseases occur in Duchenne’s dystrophy?

12. Why can cardiac disorders appear in Duchenne’s dystrophy?

13. Why are patients with Duchenne’s dystrophy often intellectually impaired?

14. What tests can help to diagnose Duchenne’s dystrophy?

15. What can physical examination reveal to confirm the diagnosis?

16. What is biopsy?

17. What can help invalids with Duchenne’s dystrophy to move?

18. At what age does death usually occur? What is its common cause?

19. Is this disease treatable?

20. Is this disease curable?

Additional Questions. Something to Think about

1. What are the most common causes of aching muscles? (clues: strains, stretching, overuse)

2. If you have not played volleyball for a season and then join in a volleyball tournament, how may your neck muscles feel the next day? (clues: sore, stiff)

3. What is the physiologic cause of sore muscles? (clues: lactic acid, overproduction)

4. How can you prevent muscle soreness? (clue: warm-ups, exercises)

5. What is hernia? (clue: rupture)

6. Where in the body do common hernias occur? (clues: groin, navel)

7. Should hernia receive medical attention at once? Why? (clues: blood supply, interference)

8. What will help prevent hernias? (clue: muscle tone)

9. Why do human beings yawn? (clues: blood, oxygen, head)

10. Why is it important to strengthen both red and white muscles? (clues: energy, endurance)

Text 6.

Subacute Bacterial Endocarditis

Subacute bacterial endocarditis is an inflammation of the inner lining of the heart or endocardium. It is caused by engraftment of Streptococcus viridans on a valve already damaged by rheumatic infection. Streptococcus viridans causes great damage to the heart valves producing lesions called vegetations. These vegetations mat break off into the bloodstream as emboli (floating clots or thrombi).

The symptoms are similar to those of any infection but are less severe than an acute endocarditis. Subacute bacterial endocarditis is characterized by fever of varying grades. Sometimes it none at all, sometimes with wide daily swings of septic type, e.g., fever may be subnormal in the morning and elevated (up to 40) in the evening. Usually fever is recurrent and followed by chills and sweats.

Subacute bacterial endocarditis is accompanied by anorexia, malaise, prostration, weight and strength loss, though at the onset the patient may experience a feeling of fatigue with little fever.

The emboli may lodge in the brain arteries resulting in ischemia and paralysis. Emboli may appear in the kidney and cause hematuria. Emboli may be accumulated in the dermal small vessels forming multiple pinpoint hemorrhages known as petechiae. When embolism starts resulting from clots in the heart, local pain and other symptoms appear depending upon the organ or body part affected. Splenic, renal and cerebral infarctions are common. With increasing anemia there may be bleeding from the nose, lungs and stomach.

When the process of healing of valvular lesions occurs, scar tissue in the valve leaflets contracts and insufficiency of the valves develops. The degree of functional valve impairment depends on the severity of endocardial lesion.

In cases when inflammatory valve lesion fails to heal during th usual period of a few months, subacute bacterial endocarditis is followed by increasing toxic state of a patient. Finally, with an increase of toxic state, weakness and mental confusion may become marked and complicated by concomitant acute myocarditis, dyspnea and hepatic pains.

A history of rheumatic fever is of diagnostic value. On auscultation a soft blowing murmur over the valve area is heard. As the mitral valve is most commonly involved, a soft systolic mitral murmur is present. A murmur alone must not be taken as positive evidence of subacute bacterial endocarditis because in any acute febrile disease, a systolic murmur may be caused by the developed cardiac dilatation. However, a murmur occurring with a rise in fever and an increase of leucocytes are proved to be of endocarditic origin.

Treatment is always conservative. Conventional antibiotic therapy is effective in curing this pathologic condition. Bed regimen, rest, balanced diet and proper nursing will lead to cure.