Recurrent transient severe hypocalcaemia in two siblings with type 1 Bartter syndrome.

Type 1 Bartter syndrome causes hypokalaemia and metabolic alkalosis owing to mutation in the SLC12A1 gene. Meanwhile, hypocalcaemia is rare in Bartter syndrome, except in type 5 Bartter syndrome. Herein, we describe two siblings with type 1 Bartter syndrome with recurrent transient severe hypocalcaemia. They each visited our hospital several times with chief complaints of numbness in the limbs, shortness of breath and tetany after stresses such as exercise or fever. Severe hypocalcaemia was also observed with a serum calcium level of approximately 6.0 mg/dL at each visit. The clinical symptoms and abnormalities in laboratory findings quickly improved with rest and intravenous treatment. In a steady state, no severe hypocalcaemia was evident, but serum intact parathyroid hormone (PTH) levels were high. In recent years, a large-scale study has revealed that type 1 and type 2 Bartter syndrome have high PTH values. In addition, there are reports that these patients develop hypocalcaemia due to PTH resistance. Therefore, our patient was also in a PTH-resistant state, and hypocalcaemia was thought to be exacerbated by physical stress. It is not well known that Bartter syndrome patients other than those with type 5 suffer from hypocalcaemia. And hypocalcaemia was not detected in normal examinations under steady-state conditions. Therefore, in patients with type 1 and type 2 Bartter syndrome, severe hypocalcaemia may occur, but may go unnoticed. When following up these patients, the attending physician must keep in mind that such patients are in a PTH-resistant state and that physical stress can cause severe hypocalcaemia.

A case of early onset cystinuria in a 4-month-old girl.

Cystinuria is an autosomal recessive disorder characterized by a decrease in the reabsorption of cystine and dibasic amino acids (lysine, ornithine, and arginine) in the renal proximal tubule. It presents with recurrent urolithiasis. Cystinuria accounts for 6-8% of all pediatric urolithiasis. The age of onset is typically 10-30 years. Here, we report a case of early-onset cystinuria. A 4-month-old girl presented with hematuria. We noticed multiple renal calculi in ultrasonography and abdominal computerized tomography scans. The diagnosis was cystinuria with urinary calculus analysis and urinary amino acid analysis. The patient was treated with urine alkalinization and cystine chelating drugs. Gene analysis showed a P482L heterozygous mutation from her mother, and an A70V heterozygous mutation from her father, in the SLC7A9 gene. This gene encodes a putative subunit of the neutral and basic amino acid transport protein, BAT1. Although cystinuria is an autosomal recessive disease, there have been previous reports of P482L heterozygous mutations greatly suppressing cystine reabsorption and causing cystinuria symptoms. Therefore, the highly influential P482L mutation of the SLC7A9 gene may have contributed to the onset of this autosomal recessive disease at an extremely young age.

An autopsy case of microencephaly, bizarre putaminal lesion, and cerebellar atrophy with heart and liver diseases.

We reported a 64-year-old autopsy case, showing a unique combination of disorders in visceral organs and brain. She had developmental delay, microencephaly, and facial dysmorphism. She developed sick sinus syndrome and liver cirrhosis. There were no abnormalities in laboratory tests for congenital metabolic errors or anomaly syndromes, including activities of lysosomal enzymes, isoelectric focusing of serum transferrin or array comparative genomic hybridization. She died of cardiorespiratory failure. At autopsy she showed liver cirrhosis and mesangial proliferation. The brain weighed 710 g. Bizarre putaminal changes were found, in which the size of area of putamen in coronal sections was small, aberrant fiber running was increased, and immunoreactivity for tyrosine hydroxylase was reduced. Loss of Purkinje cells was found throughout the cerebellar cortex. She had unreported combination of developmental delay, facial dysmorphism, small brain, bizarre putaminal lesion, cerebellar atrophy, cardiac disease, liver cirrhosis and renal disease. Although the exact cause of disease still remains to be investigated, it will be a clue for the establishment of new disease entity to accumulate subjects having the similar phenotype.

Autoimmune neurological disorders associated with group-A beta-hemolytic streptococcal infection.

Although central nervous system (CNS) disorders associated with group-A beta-hemolytic streptococcal (GABHS) infection occur only rarely, Sydenham's chorea is a well-recognized disease that can arise following infection. Children may develop a tic, obsessive compulsive disorder (OCD), and extrapyramidal movement subsequent to GABHS infection. These disorders have been termed pediatric autoimmune neuropsychiatric disorders associated with streptococci (PANDAS). Herein we report one case each of acute disseminated encephalomyelitis (ADEM), PANDAS and subacute encephalitis associated with GABHS infection. To evaluate the pathogenesis of the CNS disorders associated with GABHS infection, we measured levels of neurotransmitters, cytokines, anti-neuronal autoantibodies, and performed immunohistochemistry using patient sera to stain human brain sections. All three cases showed psychiatric behavioral disorders. Immunotherapy was effective, and homovanillic acid levels in the cerebrospinal fluid (CSF) were elevated at the acute stage in all three cases. In each case of ADEM and PANDAS, immunohistochemistry demonstrated neuronal impairment in the basal ganglia during the acute stage. Neuronal immunoreactivity was visualized in the cerebral cortex at the acute stage in the case of subacute encephalitis. There was no direct correlation between immunoreactivity of patient sera on the brain sections and positivity of anti-neuronal autoantibodies or CSF biomarkers. The results suggest that autoimmune responses may modulate neurotransmission, and the use of patient serum for immunohistochemistry is a sensitive screening method for the detection of anti-neuronal autoantibodies in CNS disorders associated with GABHS infection.

Hypoglossal hypoplasia and hyperplasia of the area postrema following perinatal hypoxic brain damage.

We report here an autopsy case of perinatal hypoxic brain damage showing hypoglossal hypoplasia and hyperplasia of the area postrema (AP) in the medulla oblongata. A 16-year-old girl who suffered from severe psychomotor developmental delay, epilepsy and tongue fasciculation, was shown by pathology to have a medullary change, as well as tongue atrophy and severe sclerotic changes in the cerebrum and cerebellum. Moderate to severe neuronal loss and gliosis were found in the brainstem. But neurons were preserved in the trigeminal nuclei, abducens nucleus and dorsal vagal nucleus. We performed a preliminary immunohistochemical analysis of sections of the medulla oblongata in our case, normal controls and disease controls with perinatal hypoxic ischemic encephalopathy (HIE). The normal and disease controls showed neither hypoglossal hypoplasia nor AP hyperplasia. The combination of hypoglossal hypoplasia and AP hyperplasia is unique and intriguing, and further analysis of the AP is required to understand developmental brain disorders.