Case report: rare skeletal manifestations in a child with primary hyperparathyroidism

Abstract

BackgroundPrimary hyperparathyroidism (PHPT) is uncommon among children with an incidence of 1:300,000. This diagnosis is often missed in children in contrast to adults where it is detected at a pre symptomatic stage due to routine blood investigations. Etiology of PHPT can be due to adenoma, hyperplasia or rarely carcinoma.Case presentationA 12 year old Sri Lankan girl presented with progressive difficulty in walking since 1 year. On examination she had bilateral genu valgum. Skeletal survey revealed valgus deformity of knee joints, bilateral subluxation of upper femoral epiphysis(SUFE), epiphyseal displacement of bilateral humeri, rugger jersey spine and subperiosteal bone resorptions in lateral aspects of 2nd and 3rd middle phalanges. There were no radiological manifestations of rickets. Metabolic profile revealed hypercalcemia with hypophosphatemia. Intact parathyroid hormone levels were elevated at 790 pg/ml. Vitamin D levels were deficient. She had low bone mineral density with Z score of −3.4. Vitamin D supplementation resulted in worsening of hypercalcemia without reduction in PTH levels. Tc 99 Sestamibi uptake scan showed abnormal tracer retention in left inferior pole of thyroid. A large parathyroid gland was removed with histology favoring parathyroid adenoma. Post operatively she developed hypocalcemia. Bilateral osteotomy was done for SUFE and further surgeries for correction of limb deformities planned.ConclusionPHPT in children is usually diagnosed late when irreversible organ damage has occurred. Children can present with non specific symptoms involving gastrointestinal, musculoskeletal, renal and neurological systems. PHPT can cause disarray in bone and epiphysis in children during pubertal growth spurt. Genu valgum and SUFE are rare skeletal manifestations in PHPT and only 10 cases of genu valgum and 9 cases of SUFE have been reported up to now. So far no cases have been reported on epiphyseal displacement of humeri. Awareness regarding the occurrence of these rare skeletal manifestations especially during puberty is important for early diagnosis to prevent irreversible outcomes.

Primary hyperparathyroidism in Chinese children and adolescents: A single‐centre experience at Peking Union Medical College Hospital

“…Theintz GE had reported a case of PHPT with clinical signs of rickets in a 15‐year‐old boy and speculated the continuous renal phosphate leak might provide condition for development of rachitic lesions in the setting of PHPT; however, no significant difference in serum phosphorus between patients with rickets/osteomalacia and those without was found in the present study. The effect of excess parathyroid hormone on the bone and epiphysis in children going through the rapid growth spurt may be one cause of the relatively high frequency of rickets in paediatric PHPT . Our study also suggests that the earlier the onset of the PHPT, the greater the impact on bone mineralization, the more susceptible the patient is to rickets, and the higher the risk of hungry‐bone syndrome postoperatively.…”

“…Asymptomatic PHPT is defined as hyperparathyroidism in the absence of specific symptoms or signs that results from hypercalcaemia or PTH excess. Rickets/osteomalacia has been reported as a rare presenting feature in paediatric PHPT . However, in a previous small case series of paediatric PHPT (n = 13) in our centre, the prevalence of rickets was up to 84.6% .…”

“…A high incidence of rickets/osteomalacia was observed in both paediatric and adult PHPT patients in our study. Rickets/osteomalacia had been reported in a few cases of paediatric PHPT from India, while being rarely mentioned in Western reports . Considering the higher prevalence of vitamin D deficiency or insufficiency in the Chinese and Indian populations compared to Western populations, vitamin D deficiency or insufficiency may be one of the contributing factors .…”

A case of primary hyperparathyroidism due to an intrathymic ectopic parathyroid adenoma in a 15-year-old boy

“…In our case, the patient did not show specific signs or symptoms except increased genu valgum. As genu valgum is a rare skeletal manifestation in children [ 11 ], PHPT is not immediately suspected in the presence of this manifestation. Children with PHPT can present with nonspecific symptoms, such as fatigue, poor appetite, weight loss, headache, polyuria, polydipsia, nausea, emesis, abdominal pain, diarrhea, depression, or joint pain [ 6 ].…”

PHPT masquerading as rickets in children and presenting with rare skeletal manifestations: Report of three cases and review of literature

“…Most of the cases of PHPT with genu valgum described so far have occurred in the period of adolescence when there is a rapid growth spurt combined with direct effect of elevated PTH on the growth plate. [ 8 9 ]…”