Lecithin-cholesterol acyltransferase (LCAT) deficiency is a rare genetic disorder that affects cholesterol metabolism.

LCAT enzyme converts cholesterol to cholesteryl esters within HDL for efficient bloodstream transport.

The two forms of LCAT deficiency are:

Familial LCAT Deficiency (FLD)

Fish-Eye Disease (FED)

Accumulation of cholesterol and phospholipids in tissues leads to symptoms including corneal opacities, anemia, proteinuria, and renal insufficiency.

FED is a partial LCAT deficiency where enzyme activity on HDL is decreased compared to beta-LCAT activity on LDL.

Inherited LCAT deficiency causes mutations in LCAT gene leads to enzyme activity reduction. Renal issues in childhood progress to ESRD in 4th or 5th decade causes morbidity and mortality.

Acquired LCAT deficiency occurs autoantibodies against LCAT leads to similar lipoprotein abnormalities as congenital deficiency.

Rare Familial LCAT Deficiency (FLD) and Fish-Eye Disease (FED) affect less than 1 in 1,000,000.

Geographic and ethnic distribution of cases widely spread with isolated occurrences reported globally.

Symptoms of the condition may appear at any age but are typically noticeable in the second or third decade.

Immunofluorescence studies are usually negative in acquired LCAT deficiency with membranous nephropathy, but some show C3 deposition.

LCAT enzyme converts free cholesterol in plasma to cholesteryl esters due to transfer of fatty acid from lecithin.

Essential reaction for high-density lipoprotein maturation and reverse transport of cholesterol from tissues to liver.

HDL particles are dysfunctional with low cholesterol levels due to lack of cholesteryl ester formation causes abnormal lipid profiles.

The causes of LCAD are:

Mutation Types

Inheritance Pattern

Pathogenic Mechanisms

Loss of Enzyme Activity

Phenotypic Variability

Residual LCAT activity varies with mutation type. Mutations allows enzyme function causes milder phenotype and better prognosis.

Renal disease severity and development impact prognosis. Early onset and rapid progression worsen outcomes.

Early symptoms in those with FLD may lead to severe disease progression and earlier renal complications.

Late-onset or mild symptoms suggest better prognosis for those with milder presentations.

Collect details including family history and symptoms progression to understand clinical history of patient.

Ocular Examination

Dermatological Examination

Abdominal Examination

Symptoms are:

Visual impairment, fatigue, jaundice, Proteinuria, renal impairment

Visual aids improve quality of life for patients with corneal opacities and vision impairment.

Manage hypertension and reduce proteinuria with ACE inhibitors or ARBs.

Regularly monitor renal function for early detection and management of renal disease; dialysis or transplant may be required.

Lipid-lowering drugs such as statins to treat dyslipidemia in LCAT deficiency even without direct impact.

Research continues enzyme replacement therapy for LCAT enzyme to improve symptoms in trials.

Endocrinology, Metabolism

Use magnifying glasses and other visual aids to help individuals with impaired vision due to corneal opacities.

Improve visibility and safety for visual impaired with better lights and colours.

Protect eyes with sunglasses to prevent UV light worsens corneal issues.

Limit salt intake to control hypertension and fluid retention effectively.

Proper awareness about LCAT should be provided and its related causes with management strategies.

Appointments with an endocrinologist and preventing recurrence of disorder is an ongoing life-long effort.

Endocrinology, Metabolism

Atorvastatin:

It blocks an enzyme required for cholesterol production to reduce cholesterol levels in the blood.

Endocrinology, Metabolism

Lisinopril:

It dilates arteries to inhibits angiotensin I conversion into angiotensin II.

Endocrinology, Metabolism

Atenolol:

It blocks response to beta-adrenergic stimulation for beta1 receptors at low doses.

Endocrinology, Metabolism

Corneal transplantation replaces damaged corneal tissue with a healthy donor cornea to improve vision and daily functions for patients.

In renal interventions, procedures like dialysis and kidney transplantation are performed.

Endocrinology, Metabolism

In the initial treatment phase, evaluation of medical history, physical examination and laboratory test to confirm diagnosis.

Pharmacologic therapy is effective in the treatment phase as it includes use of statins, antihypertensive and ACE inhibitors.

In supportive care and management phase, patients should receive required attention such as lifestyle modification and intervention therapies.

The regular follow-up visits with the endocrinologist are scheduled to check the improvement of patients along with treatment response.