| Syndrome |
clinical features |
Mechanisms |
| Type A
syndrome |
|
|
| Classic |
Acanthosis nigricans, severe
insulin |
Insulin-receptor mutations or |
| |
resistance, ovarian
hyperandrogenism |
other target-cell defects in
insulin action |
| Rabson-Medenhall |
Type A features, perhaps with
dental |
Insulin-receptor mutations or |
| |
dysplasia, pineal hyperplasia,
or other |
other target cell defects in
insulin |
| |
dysmorphic features |
action; possibly other defects |
| Pseudoarcromegaly |
Type A features, perhaps with
acral |
Possibly insulin-receptor |
| |
ment, muscle hypertrophy,
widened teeth |
mutations, other defects |
| |
spacing, muscle cramps or
other features |
|
| |
of acromegaly |
|
| Leprechaunism |
Intrauterine growth
retardation, dysmorphic |
Insulin-receptor mutations;
possible |
| |
facies, perhaps with Type A
features, |
defects in other growth-factor
|
| |
hypertrichosis, lipoatrophy,
or phallic |
receptors or pathway common to |
| |
enlargement |
multiple growth factors |
| Lipodystrophy: |
|
|
| |
Total congenital |
|
|
| |
Lipotrophy |
Total lipoatrophy, perhaps
with Type A |
Possibly insulin-receptor
mutations |
| |
features, hepatosplenomegaly,
cardio- |
or other defects |
| |
myopathy, features of
acromegaly, hyper- |
|
| |
triglyceridemia, or genital
hypertrophy |
|
| |
Partial congenital |
|
|
| |
lipodystrophy |
Adipose-tissue depots variably
affected |
Possibly insulin-receptor
mutations |
| |
by lipoatrophy or
lipohypertrophy, |
or other defects |
| |
perhaps with Type A features,
hepa- |
|
| |
tosplenomegaly,
cardiomyopathy, features |
|
| |
of acromegaly or
hypertriglyceridemia |
|
| Type C Syndrome |
| |
Severe insulin resistance, |
Insulin receptor anitbody |
| |
hyperinsulinemia,
hyperandrogenemia |
|
