The ability of mature hepatocytes to take up and conjugate bilirubin
may be exceeded by abnormal increases in erythrocyte destruction
(hemolytic jaundice) or by hepatocellular damage (functional jaundice),
such as in hepatitis. Finally, obstruction of the duct system between the
liver and duodenum (usually of the common bile duct in the adult and
rarely from aplasia of the duct system in infants) results in a backup of
bilirubin (obstructive jaundice, see question 218 and feedback).
218.The answer is d. (Kaspeer, pp 1881–1882, 1898–1899. Kumar, pp
928–931. Junqueira, pp 334–335. Guyton, pp 800–801.)The pattern of ele-
vated liver enzymes, alkaline phosphatase, and bilirubin are consistent
with obstructive jaundice (see table below). The presence of pain (in the
right upper quadrant radiating to the shoulder) after eating a meal consist-
ing of fried foods makes gallstones the most probable diagnosis. Similar
pain often occurs in these patients when they have not eaten for long peri-
ods of time and then have a large meal. The pain is caused by the obstruc-
tion of the cystic duct or common bile duct that produces increased
lumenal pressure within the bile vessels, which cannot be compensated for
by cholecytokinin-induced contractions. The pain usually lasts for one to
four hours as a steady, aching feeling. A mnemonic device for gallstones is
4F (F,F,F,F): female, forty, fat, and fertile.
Gastrointestinal Tract and Glands Answers 337Liver enzymes
(AST and ALT) ↑ ↑↑↑
Alkaline phosphatase ↑↑↑ ↑
Bilirubin ↑↑↑ ↑↑↑Enzyme Obstructive Parenchymal219.The answer is d.(Junqueira, pp 283–285. Kumar, p 774. Kasper,
p 2327.)The patient in the scenario suffers from type II dentinogenesis imper-
fecta, an autosomal dominant disorder caused by mutation in the DSPP gene.
The result is defective dentin, discoloration of the translucent teeth (blue-gray
or yellow-brown color). Those teeth are weaker than normal, making them
prone to rapid decay, wear, breakage, and loss. Type II dentinogenesis imper-
fecta occurs about 1 in 6000–8000 births. Type I occurs in conjunction with