A single centre retrospective analysis of cinacalcet therapy in primary hyperparathyroidism

Primary hyperparathyroidism (pHPT) is a common endocrine disorder that can be cured by parathyroidectomy, and patients unsuitable for surgery can be treated with cinacalcet. Availability of surgery may be reduced during COVID-19 and cinacalcet can be used as bridging therapy. In this single centre retrospective analysis, we investigated the efficacy and safety of cinacalcet in patients with pHPT receiving cinacalcet between March 2019 and July 2020, including pre-parathyroidectomy bridging. We reviewed and summarised the published literature. 86 patients were identified, with most achieving target calcium (79.1%) with a mean dose of 39.4 mg/day for a median duration of 35 weeks. Calcium normalised in a median time of 5 weeks. The majority of patients commenced cinacalcet 30 mg/day (78; 90.7%) with the remainder at 60 mg/day (8; 9.3%). 57.8% of patients commenced on lower dose cinacalcet (30 mg/day) achieved a target Ca without requiring 60 mg/day. Baseline PTH was significantly higher in patients requiring higher doses of cinacalcet (p=0.014). 18.6% of patients reported adverse reactions and 4.7% discontinued cinacalcet. Patients treated with cinacalcet pre-parathyroidectomy required a higher dose and fewer achieved target calcium compared to those treated medically with cinacalcet alone. Post-operative calcium was similar to patients not given pre-parathyroidectomy cinacalcet. In summary, cinacalcet at an initial dose of 30 mg/day is safe and effective for achieving target calcium in patients with symptomatic or severe hypercalcaemia in pHPT, including those treated pre-parathyroidectomy. We propose a PTH threshold of >30 pmol/L to initiate at a higher dose of 60 mg/day.

439 Managing Parathyroid Carcinoma in the Age of COVID 19

Aim Parathyroid carcinoma is a rare malignancy accounting for 1% of cases of primary hyperparathyroidism. Pre-operative diagnosis is difficult because in the absence of metastatic disease, the presentation is similar to benign parathyroid disease. In patients with hyperparathyroidism and severe hypercalcaemia or a significantly raised parathyroid hormone (PTH) level clinicians should consider parathyroid carcinoma and expediting surgical management. During the current pandemic, a high index of suspicion should be maintained to ensure that care is not compromised. A review of the management of patients with suspected parathyroid carcinoma during the COVID-19 pandemic is presented. Method In our tertiary referral centre for Endocrine surgery, 4 presentations of parathyroid cancer were reviewed. Their investigations, surgical management and post-operative outcomes are described with a brief literature review of parathyroid cancer. Results Of the four cases of parathyroid carcinoma described, all presented with severe hypercalcaemia and significantly raised PTH levels. Pre-operative mean calcium was 3.36mmol/L and mean PTH was 80pmol/L (52-99.8). Patients were imaged with a combination of cross-sectional imaging and ultrasound. Two patients had evidence of distant disease at presentation. 1 patient was transferred as an inpatient to our centre and the other three patients were seen within 2 weeks of referral; the mean time from referral to surgery was 14days (1-23). Post-operatively, all patients achieved normocalcaemia, with PTH levels normal in all but one. Conclusions Despite limitations on face-to-face clinic consultations and reduced capacity for elective surgery during the COVID-19 pandemic, all patients were investigated and managed promptly to ensure superior outcomes.

Symptomatic isolated axillary lymph node sarcoidosis: an unusual presentation

An 82-year-old woman admitted following a 4-week history of feeling unwell, abdominal pain and constipation. Initial investigations revealed severe hypercalcaemia with suppressed parathyroid hormone and elevated 1,25-dihydroxycholecalciferol. ACE was also raised. CT scans of the head, chest, abdomen and pelvis were normal. Fluorodeoxyglucose-positron emission tomography scan showed metabolically active right axillary lymphadenopathy which when biopsied under ultrasound guidance confirmed sarcoidosis. The patient was started on high-dose prednisolone with resolution of symptoms within 2 weeks. Isolated lymph node sarcoidosis is uncommon, and the reported usual sites are lymph nodes in the head and neck. Rarely has it been reported in the axillary lymph nodes.

Huge cutaneous abscess and severe symptomatic hypercalcaemia secondary to Mycobacterium kansasii infection in an immunocompetent patient

Mycobacterium kansasii is among the most common non-tuberculous mycobacteria causing human infections. Apart from pulmonary infection, the most common infection caused by M. kansasii is skin and soft tissue infection, and it is very rare in immunocompetent people. In this report, we present a case of a huge cutaneous abscess caused by M. kansasii. A 63-year-old man living in Bangkok presented with progressive pain at the left lateral chest wall for 3 weeks and altered mentation for a few days. Examination revealed a non-tender fluctuated cutaneous mass 20×10 cm in size. An aspiration of the mass yielded 50 mL pus with many positive acid-fast bacilli. Mycobacterial PCR was positive for M. kansasii with culture confirmation. There was severe hypercalcaemia. The treatment included surgical drainage, and medical treatment consisted of isoniazid, rifampicin, ethambutol and levofloxacin, along with adequate hydration and calcitonin for hypercalcaemia. The patient gradually improved and was discharged 12 days after hospitalisation.

Refractory hypercalcaemia associated with disseminated Cryptococcus neoformans infection

Summary Hypercalcaemia is a very common endocrine condition, yet severe hypercalcaemia as a result of fungal infection is rarely described. There are have only been two reported cases in the literature of hypercalcaemia associated with Cryptococcus infection. Although the mechanism of hypercalcaemia in these infections is not clear, it has been suggested that it could be driven by the extra-renal production of 1-alpha-hydroxylase by macrophages in granulomas. We describe the case of a 55-year-old woman with a 1,25-OH D-mediated refractory hypercalcaemia in the context of a Cryptococcus neoformans infection. She required treatment with antifungals, pamidronate, calcitonin, denosumab and high-dose glucocorticoids. A disseminated fungal infection should be suspected in immunosuppressed individuals presenting with hypercalcaemia. Learning point In immunocompromised patients with unexplained hypercalcaemia, fungal infections should be considered as the differential diagnoses; Glucocorticoids may be considered to treat 1,25-OH D-driven hypercalcaemia; however, the benefits of lowering the calcium need to be balanced against the risk of exacerbating an underlying infection; Fluconazole might be an effective therapy for both treatment of the hypercalcaemia by lowering 1,25-OH D levels as well as of the fungal infection.

Severe hypercalcaemia from ectopic intact parathyroid hormone secretion treated with continuous renal replacement therapy in a patient with two malignancies

We present a 61-year-old Caucasian woman with endometroid carcinoma as well as a poorly differentiated adenocarcinoma who developed severe hypercalcaemia in the setting of an elevated intact parathyroid hormone. The patient was hospitalised twice for her condition. During her first hospitalisation, she was diagnosed with an endometroid carcinoma and hypercalcaemia. With medical management, she had a normal calcium level on discharge. She presented 3 weeks later with hypercalcaemia and encephalopathy. This time her hypercalcaemia was refractory to medical management, and required continuous renal replacement therapy (CRRT) to normalise her serum calcium. Lung biopsy revealed a poorly differentiated adenocarcinoma, suspicious for pancreatic primary. Due to her poor prognosis, rapid elevation of calcium with each attempt to discontinue CRRT, and the poor options for treatment of her cancers, she elected to pursue hospice care.

Rhabdomyolysis and severe biphasic disturbance of calcium homeostasis secondary to COVID-19 infection

We report a case of severe hypercalcaemia secondary to rhabdomyolysis in a woman with COVID-19 (SARS CoV-2) infection. The patient presented with myalgia and anuria with an acute kidney injury requiring haemodialysis. Creatine kinase peaked at 760 000 IU/L. A biphasic calcaemic response was observed with initial severe hypocalcaemia followed by severe, symptomatic hypercalcaemia, persistent despite haemodialysis. Control of the calcium levels was achieved by continuous haemofiltration.

Incidentally discovered severe hypercalcaemia from a functioning parathyroid cyst: the limitations of intraoperative parathyroid hormone (IOPTH) monitoring

Parathyroid cysts (PCs) are rare pathologies and are typically non-functional (do not secrete parathyroid hormone (PTH)). The aetiology of PCs is highly debated, and management is complex. We present a unique case of a parathyroid adenoma contained within a functional PC and highlight the limitations of intraoperative PTH monitoring during the surgical resection of functional PCs.