Neonatal Severe Hyperparathyroidism (NSHPT): A single centre experience from Western India

Amrita Mehta; Chandrashekhar Sudha Rao; Rachna Keshwani; Shagun Walia; Rajesh Joshi

Introduction: NSHPT is a rare, autosomal recessive inherited, disorder of CASR gene presenting as severe hypercalcemia early in life. Diagnosis requires a high index of suspicion. Intensive medical management with calcium lowering drugs should be tried prior to parathyroidectomy.

Aims: To study the clinical-laboratory-genetic profile, management and short-term outcome of children with NSHPT diagnosed at our center in the last 10 years.

Methods: Retrospective analysis of medical records of 5 cases diagnosed as NHSPT in the last decade to capture presentation characteristics, laboratory parameters, genetic mutations found, details of medical and surgical management and short term follow up as a descriptive study.

Table 1 – Profile of children with NSHPT
Case No	Age at presentation (months)	Sex	Presenting Symptoms	Total serum Calcium mg/dl (iCalcium) (mmol/l)	iPTH pg/ml (N:15-69)	CSR mutation	Post operative Outcome
1	3	M	FTT, LRTI, Polyuria,	14.1	1046.6	Compound heterozygous loss of function mutation in CASR gene	On Cinacalcet
2	8	M	FTT, polyuria irritability	24 (3.18)	556.9	Homozygous mutation CASR (+) gene	On calcium and calcitriol supplements
3	11	M	FTT, respiratory distress	22.9 (3.56)	487	Homozygous mutation CASR (+) gene	On calcium and calcitriol supplements
4	4	F	FTT, LRTI, vomiting, irritability	21 (3.42)	606.2	Homozygous mutation CASR (+) gene	Died to intercurrent illness Normal postop PTH and calcium
5	1	F	FTT, LRTI	31(>6)	873	Homozygous mutation CASR (+) gene	died due to sepsis Normal postop PTH and calcium
FTT – Failure to thrive, LRTI- Lower respiratory tract infection

Results: Five infants, 3 Male, presented between 1 to 11months of age with failure to thrive and respiratory symptoms. All were born of consanguineous union. All had severely elevated serum calcium levels and elevated intact parathyroid hormone (iPTH) levels. NSHPT was proven by mutation studies in all (Table 1). Medical treatment including hydration, diuretics, calcitonin, cinacalcet, bisphosphonate and low calcium feeds was the standard of care to lower serum calcium levels. However, all infants needed total parathyroidectomy. Transcervical thymectomy, and an additional hemithyroidectomy was done in one of them. One child had to undergo a redo surgery. Postoperatively, 2 cases had hypocalcaemia requiring calcium and calcitriol supplements, 1 required cinacalcet and 2 succumbed to sepsis and respiratory illness.

Conclusion: Children presenting with NHSPT require emergency medical management for the hypercalcemia. In most patients, a total parathyroidectomy is necessary. Treatment with cinacalcet is reported to be effective in cases with heterozygous Arg185Gln mutations of CASR gene.

IMPE Abstracts

P30