An Interesting Case of Familial Homozygous Hypercholesterolemia-A Brief Review. Indian J Clin Biochem. 2012;27:309-313. [PMID: 26405394 DOI: 10.1007/s12291-011-0165-8]

Dyslipidemia in Infants: Challenges in Diagnosis and Management

Dyslipidemia in infants is a rare condition characterized by abnormal levels of lipids in the blood, such as cholesterol and triglycerides. Early diagnosis poses a challenge due to nonspecific symptoms and lipid criteria differing from adults. Through two clinical cases of familial dyslipidemia (Type 1 Familial Hypercholesterolemia and Type 2b Combined Familial Hyperlipidemia), we highlight the diagnostic and therapeutic challenges encountered in infants, emphasizing the importance of a multidisciplinary approach in care and early screening. In the first case, a 3-month-old boy with a family history of dyslipidemia was diagnosed during bronchiolitis, revealing milky serum, pseudohyponatremia, and abnormal lipid profile. His Type 1 familial hyperlipidemia was confirmed by lipid electrophoresis. Despite dietary management and breastfeeding, he developed severe pancreatitis, successfully treated with intensive care. The second case involved a girl who presented at 3 months with vomiting and irritability. Laboratory tests indicated pseudohyponatremia, hematologic abnormalities, and lipid disturbances. Her Type 2b familial hyperlipidemia was confirmed by lipid electrophoresis. She responded well to a specialized diet, experiencing few pancreatitis episodes without meeting clinical or radiological severity criteria.

Pleomorphic cutaneous xanthomas disclosing homozygous familial hypercholesterolemia

Homoxygous Familial Hypercholesterolemia is characterized by a presence of several types of cutaneous xanthomas with an abnormal lipid profile. Some of these could be pathognomonic. Although these could be initially interpreted as isolated and localized benign disorders and offered surgical treatment, it has become increasingly clear that they could be a part of a systemic pathology. Here we describe a case of this rare disorder in a 19 years old non-obese young man who presented multiple, intertriginous, tuberous and tendinous xanthomas and had an associated abnormal lipid profile with elevated low-density lipoprotein cholesterol levels. A detailed history with clinical assessment in the differential diagnosis and laboratory investigations led to a precise diagnosis.

Spectrum of mutations in homozygous familial hypercholesterolemia in India, with four novel mutations

BACKGROUND AND AIMS

Homozygous familial hypercholesterolemia (FH) is a rare but serious, inherited disorder of lipid metabolism characterized by very high total and LDL cholesterol levels from birth. It presents as cutaneous and tendon xanthomas since childhood, with or without cardiac involvement. FH is commonly caused by mutations in three genes, i.e. LDL receptor (LDLR), apolipoprotein B (ApoB) and PCSK9. We aimed to determine the spectrum of mutations in cases of homozygous FH in Asian Indians and evaluate if there was any similarity to the mutations observed in Caucasians.

METHODS

Sixteen homozygous FH subjects from eleven families were analyzed for mutations by Sanger sequencing. Large rearrangements in LDLR gene were evaluated by multiplex ligation probe dependent amplification (MLPA) technique.

RESULTS

Ten mutations were observed in LDLR gene, of which four mutations were novel. No mutation was detected in ApoB gene and common PCSK9 mutation (p.D374Y). Fourteen cases had homozygous mutations; one had compound heterozygous mutation, while no mutation was detected in one clinically homozygous case. We report an interesting "Triple hit" case with features of homozygous FH.

CONCLUSIONS

The spectrum of mutations in the Asian Indian population is quite heterogeneous. Of the mutations identified, 40% were novel. No mutation was observed in exons 3, 9 and 14 of LDLR gene, which are considered to be hot spots in studies done on Asian Indians in South Africa. Early detection followed by aggressive therapy, and cascade screening of extended families has been initiated to reduce the morbidity and mortality in these patients.