MDS PREP
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.
Crepitus will be seen in the tissues surrounding an infection by
1) Staphylococcus
2) Streptococcus
3) Clostridium tetani
4) C. perfringes
General Medicine
Answer: 4
Crepitus is a characteristic sign of gas gangrene, which is often caused by Clostridium perfringens. This bacterium produces gas in tissues, leading to a crackling sensation upon palpation.
Black urine is seen in
1) Billirubinuria
2) Blackwater fever
3) Alkaptonuria
4) All
General Medicine
Answer: 4
Black urine can be associated with several conditions:
Bilirubinuria: The presence of bilirubin in urine can
lead to dark urine, although it is typically more yellow-brown than black.
Blackwater fever: This is a severe complication of
malaria that can cause hemolysis and dark urine due to the presence of
hemoglobin.
Alkaptonuria: This is a rare genetic disorder where
homogentisic acid accumulates in the body, leading to dark urine upon
exposure to air.
A newborn baby has severe bleeding. Which of the following coagulation factor deficiencies is the most common cause of this condition?
1) Factor II deficiency
2) Factor V deficiency
3) Factor VIII deficiency
4) Factor X deficiency
In newborns, factor VIII deficiency, known as Hemophilia A, is the most common cause of severe bleeding. It is an X-linked recessive disorder, which means that females are carriers and males are affected. The severity of the bleeding is indicative of the lack of this crucial coagulation factor.
A patient with a rare bleeding disorder has a prolonged aPTT and a prolonged PT. Which coagulation factor is likely deficient?
1) Factor V
2) Factor VIII
3) Factor X
4) Factor XII
Both the aPTT (activated Partial Thromboplastin Time) and PT (Prothrombin Time) are prolonged in the case of factor VIII deficiency, which is characteristic of Hemophilia A. This is because factor VIII is involved in both the intrinsic and common pathways of the coagulation cascade.
Not true about trigeminal neuralgia is
1) Mainly in middle aged and elderly
2) Paroxysms of pain last only a few seconds
3) Opthalmic division is usually affected first
4) None of the above
General Medicine
Answer: 3
Trigeminal neuralgia typically involves the maxillary and mandibular divisions more than the ophthalmic division; thus, it is incorrect to state that the ophthalmic division is usually affected first.
A patient with chronic lymphocytic leukemia (CLL) is found to have a very high white blood cell (WBC) count. Which of the following is NOT a common physical examination finding in CLL?
1) Splenomegaly
2) Lymphadenopathy
3) Hepatomegaly
4) Fever
Chronic lymphocytic leukemia is characterized by the accumulation of mature-looking but functionally incompetent lymphocytes in the blood, bone marrow, and lymphoid tissues. Common physical examination findings include splenomegaly, lymphadenopathy, and hepatomegaly due to infiltration by leukemic cells.
What is the primary diagnostic difference between constitutional delay of growth and growth hormone deficiency?
1) Family history
2) Epiphyseal development
3) Birth weight and height
4) GH receptor sensitivity
Constitutional delay of growth is characterized by a positive family history of late maturation, while growth hormone deficiency typically is not associated with such a family pattern.