MDS PREP
A 55-year-old male with a history of alcoholism presents with a chronic non-healing ulcer on his lower leg. The ulcer has a necrotic center surrounded by erythematous tissue. Which of the following is the most likely diagnosis?
1) Arterial ulcer
2) Venous stasis ulcer
3) Pressure ulcer
4) Neuropathic ulcer
The chronic non-healing nature of the ulcer and its location on the lower leg in an individual with a history of alcoholism are more consistent with a neuropathic ulcer. Neuropathy due to chronic alcohol use can lead to loss of protective sensation and poor blood supply, resulting in these types of ulcers.
What is the characteristic histological feature of the polyps in Peutz-Jeghers syndrome?
1) Adenomatous changes
2) Papillomatous structure
3) Arborizing network of connective tissue and smooth muscle
4) High-grade dysplasia
The polyps in Peutz-Jeghers syndrome are typically large and pedunculated with a lobulated contour. Histologically, they exhibit a characteristic arborizing network of connective tissue, smooth muscle, lamina propria, and glands lined by normal appearing intestinal epithelium.
What is the most common complication of the nephrotic syndrome?
1) Hyperkalemia
2) Hypocalcemia
3) Thrombocytopenia
4) Hypertension
Hypertension is a common complication of the nephrotic syndrome due to the loss of protein in the urine, particularly albumin, which leads to decreased plasma oncotic pressure and subsequent fluid retention and increased blood volume.
What is the most common site for hydatid cyst formation in humans?
1) Brain
2) Lung
3) Liver
4) Spleen
Hydatid disease, caused by Echinococcus granulosus, primarily affects the liver in approximately 70% of cases. This is because the ova ingested by humans are carried to the liver via the portal venous system, where they are trapped and develop into cysts.
What is the most common cause of death in patients with anaphylactic shock?
1) Respiratory failure due to bronchoconstriction
2) Cardiac arrest due to arrhythmias
3) Seizures
4) Stroke
The most common cause of death in anaphylactic shock is respiratory failure resulting from bronchoconstriction and laryngeal edema. Immediate airway management and bronchodilation are critical in the treatment of anaphylaxis.
In emphysema, the dilatation occurs
1) Beyond major bronchus
2) In alveolar region
3) Beyond terminal bronchioles
4) Beyond minor bronchus
General Medicine
Answer: 3
In emphysema, the dilatation occurs beyond terminal bronchioles
What is the primary mechanism of action of antihistamines in the management of anaphylaxis?
1) Blocking the release of mediators from mast cells
2) Directly counteracting the effects of histamine on H1 receptors
3) Acting on beta-2 adrenergic receptors to dilate bronchioles
4) Inhibiting the production of leukotrienes and prostaglandins
Antihistamines, particularly H1 blockers, are used to counteract the vasodilatory and bronchoconstrictive effects of histamine in anaphylaxis.
What is the primary source of vitamin D3 in humans?
1) Diet
2) Skin synthesis from sunlight
3) Intestinal bacteria
4) Supplementation
The precursor of vitamin D3, 7-dehydrocholesterol, is present in the keratinocytes of the skin's stratum corneum. Upon exposure to UV light, it is converted into cholecalciferol (vitamin D3).