easy Qs - kashmala

[ArchivalUser]

A 50-year-old male has a 35-year history of diabetes
mellitus. During this time, his disease has been poorly
controlled. He now has problems with sexual function,
including difficulty attaining an erection. He is also
plagued by a mild but recurrent, low-volume diarrhea
and by difficulty with urination. These problems stem
from which of the following mechanisms of cellular

injury?

A.Coagulative necrosis
B.Sorbitol accumulation
C.Nonenzymatic glycosylation
D.Leukocytic infiltration
E.Hyaline deposition

A 40-year-old male has been taking daily insulin in-
jections for the past 25 years. When he does not show up
for work, a friend visits his house, finds him on the floor
in an obtunded state, and calls an mnbulance. On admis-
sion to the hospital, the patient has a hemoglobin
concentration of 8.9%, a serum glucose level of 11 mg/dL,
a serum osmolality of 295 mOsm/kg, and a urinalysis that
reveals 4+ ketonuria with specific gravity of 1.010. Which
of the
ings?
O

following statements best characterizes these find-

A.He is in poor control and has had an insulin over-
dose.
B.He is in good control but has developed ketoacido-
sis.
C.He is in poor control and is not taking his insulin.
D.He is in good control but has not eaten food re-
cently.
E.He is in poor control and has developed hyperos-
molar coma.

[ArchivalUser]

1.C
2.D

[ArchivalUser]

(B) This patient has autonomic neuropathy caused by
long-standing diabetes. It is thought that nerve cells do not
require insulin for glucose uptake. In the presence of hy-
perglycemia, too much glucose diffuses into cell cytoplasm
and accumulates. The excess glucose is metabolized by
intracellular aldose reductase enzyme to sorbitol and then
to fructose. This increased carbohydrate increases cellular
osmolarity and increases free water influx, injuring the cell.
Schwann cells are injured in this manner, leading to pe-
ripheral neuropathy. Coagulative necrosis in diabetics is
most likely to result as a complication of atherosclerosis.
Glycosylation tends to affect vascular walls and promote
atherosclerosis. Infections with inflammation are more
common in diabetics but do not lead to the characteristic
neuropathy. Hyalinization affects small blood vessels, not
nerves.

(A) The increased hemoglobin A,c level suggests that
he has poorly controlled hyperglycemia. The profound hy-
poglycemia is consistent with overdose of insulin, and the
ketonuria suggests that he has not been eating any food. If
he had not been taking his insulin, the glucose should be
higher, and if this were coupled with ketonuria, a diagnosis
of ketoacidosis could be made. Because the serum osmolar-
ity and the glucose are not increased, he does not have
hyperosmolar coma.

[ArchivalUser]

thanks for the que....nice ones