Pseudohypoaldosteronism in a newborn male with functional polymorphisms in the mineralocorticoid receptor genes

Hyponatremia and hyperkalemia in infancy can be attributed to various causes, originating from a variety of renal and genetic disorders. Pseudohypoaldosteronism type 1 (PHA1) is one of these disorders, causing mineralocorticoid resistance that results in urinary salt wasting, failure to thrive, metabolic acidosis, and dehydration. PHA1 is heterogeneous in etiology. Inactivating mutations in the NR3C2 gene (4q31.1), which encodes the mineralocorticoid receptor, causes a less severe autosomal dominant form that is restricted to the kidney, while mutations in the amiloride-sensitive epithelial sodium channel gene (alpha subunit=SCNN1A, 12p13; beta subunit=SCNN1b, 16p12.2-p12.1; gamma subunit=SCNN1G, 16p12) causes a more severe autosomal recessive form, which has systemic effects. Here we report a neonatal case of kidney restricted PHA1 (renal type of PHA1) who first showed laboratory abnormalities before obvious PHA1 manifestations, with two functional polymorphisms in the NR3C2 gene. This is the second genetically confirmed case in Korea and the first to show functional polymorphisms that have previously been reported in the literature.

A Case of Hypereosinophilic Syndrome with Bladder Involvement in a 7-Year-Old Boy

Hypereosinophilic syndrome (HES) is characterized by the presense of hypereosinophilia with evidence of target organ damage. We report a patient diagnosed with eosinophilic cystitis and HES. A 7 year old boy had hematuria, dysuria, and increased urinary frequency for 1 day. Laboratory examinations revealed hypereosinophilia (eosinophils, 2,058/microL), hematuria, and proteinuria. Abdominal sonography revealed diffuse and severe wall thickening of the bladder. The patient was treated initially with antibiotics. However, his symptoms did not improve after 7 days. A computed tomography scan demonstrated severe wall thickening of the bladder and the hypereosinophilia persisted (eosinophils, 2,985/microL). The patient complained of chest discomfort, dyspnea, epigastric pain, and vomiting on hospital day 10. Parasitic, allergic, malignancy, rheumatologic, and immune workups revealed no abnormal findings. Chest X-rays, electrocardiography, and a pulmonary function test were normal; however, the hypereosinophilia was aggravated (eosinophils, 3,934/microL). Oral deflazacort was administered. A cystoscopic biopsy showed chronic inflammation with eosinophilic infiltration. The patient's respiratory, gastrointestinal, and urinary symptoms improved after 6 days of steroids, and he was discharged. The eosinophil count decreased dramatically (182/microL). The hypereosinophilia waxed and waned for 7 months, and the oral steroids were tapered and stopped. This case describes a patient diagnosed with eosinophilic cystitis and HES.

A Case of Primary Angiitis of the Central Nervous System: A Case Presentation

Primary angiitis of the central nervous system (PACNS) is a rare idiopathic disorder with recurrent vasculitis restricted to the central nervous system (CNS) and involves small-sized (and at time medium-sized) blood vessels. The typical clinical manifestations include multifocal strokes or encephalopathy, often associated with severe headaches. There are very few pediatric cases with PACNS reported in the literature. The diagnosis of PACNS is mainly based on its clinical features, demonstration of angiitis on angiography or biopsy, and exclusion of secondary causes of angiitis. A high index of suspicion is necessary for the diagnosis. Though the prognosis is generally poor, use of steroids and immunosuppressive therapy has been useful in achieving successful remission in many patients. We report the case of a patient with PACNS presenting recurrent headaches for 5 days.