Concordant nephrotic syndrome in twins with PAX2 and MYO1E mutations

INTRODUCTION

The medical literature is scant with reports of twins diagnosed with nephrotic syndrome associated with genetic mutations. Mutations in the protein coding paired box gene 2 (PAX2) and in the non-muscle class I myosin, myosin 1E, (MYO1E) have been implicated in the development of steroid-resistant nephrotic syndrome. We describe the first case, to our knowledge, of the concordant presentation of nephrotic syndrome in twins with simultaneous mutations in PAX2 and MYO1E.

CASE REPORT

At 32 months and 33 months of age, monochorionic, diamniotic twin girls presented with nephrotic syndrome. Each twin experienced three relapses during or after completion of corticosteroid treatment. Sustained remission was achieved with tacrolimus. Genetic testing of each twin revealed two heterozygous mutations of MYO1E and one homozygous mutation of PAX2. Renal biopsy results of one twin revealed pathologic findings consistent with minimal change nephropathy. The twins' phenotypes have been essentially identical.

CONCLUSION

Our cases add to the scant medical literature addressing nephrotic syndrome in twins with genetic mutations. Close monitoring of our unique patients will provide novel information about the clinical significance of combined mutations in PAX2 and MYO1E.

Infantile Primary Hyperoxaluria Type 1 Treated With Lumasiran in Twin Males

Primary hyperoxaluria type 1 (PH1) is a rare genetic disease that results in oxalate overproduction leading to nephrolithiasis (NL), nephrocalcinosis (NC), kidney failure, and systemic oxalosis. Infantile PH1 is its most severe form, and it may require intensive hemodialysis followed by a liver-kidney transplant. Lumasiran is an RNA interference (RNAi) therapeutic agent that reduces hepatic oxalate production, which has been recently approved for the treatment of PH1. In this report, we present a case of twin males with infantile PH1 and bilateral NL and NC who were treated with lumasiran at 12 months of age. Their symptoms abated after therapy was started without disease progression. To the best of our knowledge, this is the first report of PH1 occurring in twins and the first report on using lumasiran to treat infantile PH1 outside of a clinical trial. Lumasiran appears to be a successful therapeutic option for infantile PH1.

Enuresis Management in the Primary Care Pediatrics Clinic

Enuresis is a frequent complaint not always volunteered by parents or patients. The pediatric clinician has to inquire about enuresis to break the secrecy surrounding this symptom that could be related to a more serious underlying renal, endocrine, or psychosocial disease. Determining the type of enuresis is crucial to offer optimal treatment. We present a review for the pediatric clinician to optimize their care of the child with monosymptomatic enuresis. [Pediatr Ann. 2018;47(10):e390-e395.].