1/2. Central corneal mosaic opacities in Schnyder's crystalline dystrophy.PURPOSE: To report an unusual presentation of Schnyder's corneal crystalline dystrophy (SCCD), sharing the feature of central corneal mosaic opacities. DESIGN: Observational case report. methods: A 51-year-old man and his family members were examined. Investigations included slit-lamp biomicroscopy, radiography of knee joint, plasma lipid level, and genotyping of the SCCD candidate region in chromosome 1p34.1-1p36. RESULTS: A symmetric, central, disciform, full-thickness opacity was seen in both corneas of the patient. The opacities appeared in a mosaic pattern, instead of collections of crystals or a diffuse haze as typically detected in SCCD. Small clumps of crystalline deposits and arcus lipoides were also observed. Systemically, hyperlipidemia and bilateral genu valgus were identified. He had 2 daughters, and both of them had bilateral corneal crystalline deposits and genu valgus. No other family members had findings suggesting SCCD. The genetic study demonstrated that all of the affected individuals shared a common haplotype within the region of previously reported SCCD locus. However, 1 unaffected sibling of the proband also had the same haplotype. CONCLUSIONS: Central corneal mosaic opacities may be another variant of SCCD.- - - - - - - - - - ranking = 1keywords = arcus (Clic here for more details about this article) |
2/2. Delayed low density lipoprotein (LDL) catabolism despite a functional intact LDL-apolipoprotein B particle and LDL-receptor in a subject with clinical homozygous familial hypercholesterolemia.We identified a 38-yr-old male patient with the clinical expression of homozygous familial hypercholesterolemia presenting as severe coronary artery disease, tendon and skin xanthomas, arcus lipoides, and joint pain. The genetic trait seems to be autosomal recessive. Interestingly, serum concentrations of cholesterol responded well to diet and statins. We had no evidence of an abnormal low density lipoprotein (LDL)-apolipoprotein B (apoB) particle, which was isolated from the patient using the U937 proliferation assay as a functional test of the LDL-binding capacity. The apoB 3500 and apoB 3531 defects were ruled out by PCR. In addition, we found no evidence for a defect within the LDL-receptor by skin fibroblast analysis, linkage analysis, single-strand conformational polymorphism and Southern blot screening across the entire LDL-receptor gene. The in vivo kinetics of radioiodinated LDL-apoB were evaluated in the proband and three normal controls, subsequently. The LDL-apoB isolated from the patient showed a normal catabolism, confirming an intact LDL particle. In contrast the fractional catabolic rate (d-1) of autologous LDL in the subject and the normal controls revealed a remarkable delayed catabolism of the patient's LDL (0.15 vs. 0.33-0.43 d-1). In addition, the elevation of LDL-cholesterol in the patient resulted from an increased production rate with 22.8 mg/kg per day vs. 12.7-15.7 mg/kg per day. These data indicate that there is another catabolic defect beyond the apoB and LDL-receptor gene causing familial hypercholesterolemia.- - - - - - - - - - ranking = 1keywords = arcus (Clic here for more details about this article) |