Abstract

Background: To study serum insulin levels and atherosclerotic markers in patients with
acanthosis nigricans in a rural tertiary care center.
Materials and Methods: It was a Cross sectional study. The study was conducted in the
Departments of Biochemistry and Dermatology, Venereology, Leprosy (DVL), at
Kamineni Institute of Medical Sciences, India.
Results: Total number of patients recruited for the study was 50. Mean age of the
patient was 26.8 years. Females (60%) have outnumbered males (40%). Overall
majority of the acanthosis nigricans patients were students (46%). Among females
majority of them were housewives (22%). In a majority of the patients, neck was the
initial site of darkening (82%). Most of them have duration of darkening of skin for
more than one year (64%) and 84% of the patients had an insidious onset. Forty six
percent of patients had associated medical illness such as hypothyroidism (22%),
diabetes mellitus (10%), hypertension (8%), polycystic ovarian syndrome (4%),
psoriasis (2%). Neck(98%) is the most common site of acanthosis nigricans followed by
axilla(88%); elbow(42%); periorbital region(36%); groin(34%); knees(24%);
temples(22%); infralabial region(20%); antecubital fossa(14%); perioral and perinasal
(12% each); knuckles(10%); skin over hyoid bone(8%); sides of waist and
inframammary areas(6% each) and popliteal fossa(2%). Out of 50 patients, raised
serum insulin levels seen in 54% patients, of which 42% are non-diabetics and 12% are
diabetics. Also, 96% had normal fasting blood sugars (FBS <110mg/dL), 80% had
normal postprandial blood sugars (PPBS <140mg/dL). All patients (100%) had normal
total cholesterol (< 250mg/dL), 80% patients had normal HDLc (>35mg/dL), 98% had
normal LDLc (< 130mg/dL), 80% had normal triglycerides (<160mg/dL), 86% had
normal VLDLc < 40mg/dL, out of the total 50 patients with acanthosis nigricans.
Conclusion: Hypothyroidism was present in 22% of the patients with acanthosis
nigricans whereas diabetes mellitus was present in 10% of the patients with acanthosis
nigricans. Levels of fasting serum insulin were raised in 54% of patients having burke’s
neck severity score of 2, 3, 4 and neck texture score of 2,3 and axilla severity score of 2,3
in patients with acanthosis nigricans. About 20% of studied patients had decreased
HDL cholesterol levels(<35 mg/dL and increased serum triglycerides(>160 mg/dL).