Hypercalcemia and CYP24A1 Gene Mutation Diagnosed in the 2nd Trimester of a Twin Pregnancy: A Case Report.

BACKGROUND Loss-of-function mutations of the CYP24A1 gene cause a deficiency of the CYP24A1 enzyme, which is involved in the catabolism of 1,25-dihydroxyvitamin D3. Patients who are CYP24A1 enzyme deficient are at increased risk of developing hypercalcemia during pregnancy and should avoid additional vitamin D supplementation. This case report provides additional information for managing and diagnosing patients with a CYP24A1 gene mutation. CASE REPORT A primipara woman with a twin pregnancy was admitted to our hospital for frequent hypertensive crises. She had no history of hypercalcemia-associated signs and symptoms except nephrocalcinosis, and reported no other abnormalities or discomfort at presentation. Laboratory tests revealed that the parathyroid hormone level was suppressed and the serum calcium level was markedly increased. The 25-hydroxyvitamin D level was at the upper limit of the reference range while the 1,25-dihydroxyvitamin D3 level was elevated, suggesting a vitamin D catabolism disorder. A genetic test was performed and a homozygous likely pathogenic variant (based on the American College of Medical Genetics and Genomics guidelines) c.964G>A (p.Glu322Lys) was detected in the CYP24A1 gene (NM_000782.5). A cesarean section delivery was performed due to a single intrauterine demise at 33 weeks of gestation. The preterm newborn was diagnosed with transitional hypercalcemia and hyperphosphatemia; however, he was not treated, as he was asymptomatic. CONCLUSIONS Patients with a CYP24A1 gene mutation are at increased risk of hypercalcemia and fetal demise; therefore, 25-hydroxyvitamin D and calcium levels should be monitored in routine blood tests during pregnancy. Hypercalcemia in a newborn should be carefully evaluated and treated, as hypercalciuria can lead to nephrocalcinosis.

Stauffer's Syndrome in Patient with Metastatic Prostate Cancer.

Cholestasis is a symptom that can be present in many conditions, such as bile duct obstruction by malignant mases, obstruction by gallstone, acute and chronic viral hepatitis, and autoimmune disorders, such as primary biliary and sclerosing cholangitis. Stauffer syndrome is a rare type of paraneoplastic syndrome that presents as cholestasis with absence of underlying disease. Classically Stauffer syndrome has been described in renal cell cancer patients. In literature cholestasis as manifestation of paraneoplastic syndrome has also been described in patients with prostate adenocarcinoma and pancreatic and bronchogenic carcinoma. Conclusions. Stauffer syndrome should be kept in mind in patients who present with cholestasis with no underlying cause. We advise to exclude any possible causes of cholestasis, for example, obstruction of bile duct.