A patient was diagnosed with isolated increase in LDL. His father and brother had the same disease with increased cholesterol. The likely diagnosis is
**Core Concept**
Familial hypercholesterolemia (FH) is a genetic disorder characterized by high levels of low-density lipoprotein (LDL) cholesterol due to mutations in the LDL receptor gene, leading to impaired clearance of LDL from the bloodstream.
**Why the Correct Answer is Right**
The patient's family history of increased cholesterol levels, particularly in first-degree relatives (father and brother), is a strong indicator of a genetic component to the disease. This pattern of inheritance is consistent with an autosomal dominant pattern, where a single copy of the mutated gene is sufficient to cause the condition. The isolated increase in LDL cholesterol levels in the patient further supports the diagnosis of familial hypercholesterolemia.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is not a relevant diagnosis for isolated increase in LDL cholesterol.
**Option B:** This option does not match the clinical presentation of isolated increase in LDL cholesterol.
**Option C:** This option is not supported by the family history and clinical presentation of the patient.
**Clinical Pearl / High-Yield Fact**
Familial hypercholesterolemia is often associated with premature coronary artery disease, and early diagnosis and treatment are crucial to prevent cardiovascular complications.
**Correct Answer: C. Familial Hypercholesterolemia**