Two cases of carbonic anhydrase VA deficiency-An ultrarare metabolic decompensation syndrome presenting with hyperammonemia, lactic acidosis, ketonuria, and good clinical outcome.

The combination of neonatal hyperammonemia, lactic acidosis, ketonuria, and hypoglycemia is pathognomonic for carbonic anhydrase VA (CA-VA) deficiency. We present two cases of this rare inborn error of metabolism. Both newborns with South Asian ancestry presented with a metabolic decompensation characterized by hyperammonemia, lactic acidosis and ketonuria; one also had hypoglycemia. Standard metabolic investigations (plasma amino acids, acylcarnitine profile, and urine organic acids) were not indicative of a specific organic aciduria or fatty acid oxidation defect but had some overlapping features with a urea cycle disorder (elevated glutamine, orotic acid, and low arginine). Hyperammonemia was treated initially with nitrogen scavenger therapy and carglumic acid. One patient required hemodialysis. Both have had a favorable long-term prognosis after their initial metabolic decompensation. Genetic testing confirmed the diagnosis of carbonic anhydrase VA (CA-VA) deficiency due to biallelic pathogenic variants in CA5A. These cases are in line with 15 cases previously described in the literature, making the phenotypic presentation pathognomonic for this ultrarare (potentially underdiagnosed) inborn error of metabolism with a good prognosis.

Stenotrophomonas maltophilia Meningitis in a Term Healthy Neonate: A Case Report and Literature Review.

Stenotrophomonas maltophilia is an environmental bacterium of growing concern due to its multidrug resistance and pathogenic potential. It is considered an opportunistic pathogen of nosocomial origin most of the time, targeting a specific patients' population. We describe a case of a previously healthy full-term neonate who was found to have S. maltophilia meningitis and was successfully treated with a combination of Trimethoprim-Sulfamethoxazole and Ciprofloxacin.

ATP13A2 novel mutations causing a rare form of juvenile-onset Parkinson disease.

Parkinson disease is a common neurodegenerative disease that typically starts around the age of 60 years; however, juvenile-onset disease can occur rarely. Although Parkinson disease is typically sporadic; in rare occasions, it can be caused by a single gene defect that is inherited in an autosomal dominant, autosomal recessive, or X-linked manner. Herein, we describe a 10-year-old child who had juvenile-onset parkinsonism with rigidity, bradykinesia, dystonia, gait disturbance, and cognitive impairment. Whole exome sequencing showed compound heterozygosity for two previously unreported novel mutations in ATP13A2 (PARK9): a paternally inherited c.1321A>T (p.I441F) and a maternally inherited c.3205G>A (p.A1069T). ATP13A2 mutations are rare cause of autosomal recessive juvenile-onset Parkinson disease. Family co-segregation study and the clinical phenotype support that p.I441F and p.A1069T are indeed disease-causing mutations.