Background Osteogenesis imperfecta (OI) is a rare, connective tissue disorder characterised by bone fragility, resulting in recurrent fractures and skeletal deformities. Extra-skeletal manifestations include dentinogenesis imperfecta, hearing abnormalities and lung disease. These co-morbidities combined with recurrent fractures can exert a significant impact on health-related quality of life (HR-QOL). It is important to assess HR-QOL throughout adulthood because the prevalence of some OI-specific complications increases with age. Methods PubMed, EMBASE and CENTRAL databases were searched on 2nd February 2022 to identify studies reporting quantitative assessments of HR-QOL in adults with OI. The primary endpoint was to determine the impact of an OI diagnosis on adult’s HR-QOL. Secondary endpoints were to (i) examine how frequently various HR-QOL assessment tools were used (ii) identify differences in HR-QOL between OI types and (iii) investigate the determinants of HR-QOL in adults with OI. Search results were exported to Endnote where two reviewers independently conducted title/abstract and full-text reviews. Data from accepted studies were extracted into Microsoft Excel. A narrative synthesis was then undertaken. Results The review identified 17 studies with a total of 1,648 adults. The Short Form-36 (SF-36) was the most frequently reported HR-QOL assessment tool and was used in nine studies. Physical HR-QOL was reduced in adults with OI. Physical component scores (PCS) or individual physical domains of the SF-36 were lower in eight of nine studies. Mental component scores (MCS) were preserved in all six studies, however individual mental health domains of the SF-36 were reduced in some studies. The prevalence of anxiety/depression was relatively low in adults with OI. Those with type III OI had lower physical and respiratory HR-QOL but preserved mental HR-QOL compared with type I. The prevalence of fatigue and pain was higher in adults with OI compared with reference populations. Age and cardio-pulmonary co-morbidities were associated with lower HR-QOL. Conclusion OI in adulthood has a wide-ranging negative impact on HR-QOL. Physical and respiratory HR-QOL were lower, while the prevalence of pain and fatigue were higher than in reference populations. Mental HR-QOL was relatively preserved, although some deficits were identified. Age and cardio-pulmonary co-morbidities were associated with lower HR-QOL.

Summary Thyroid dysfunction is among the most common immune-related adverse reactions associated with immune checkpoint inhibitors. It most commonly manifests as painless thyroiditis followed by permanent hypothyroidism. This usually causes mild toxicity that does not interfere with oncological treatment. In rare instances, however, a life-threatening form of decompensated hypothyroidism called myxoedema coma may develop. We present a case of myxoedema coma in a woman in her sixties who was treated with a combination of CTLA-4 and PD-1 immune checkpoint inhibitors; for stage four malignant melanoma. She became hypothyroid and required thyroxine replacement after an episode of painless thyroiditis. Six months after the initial diagnosis of malignant melanoma, she presented to the emergency department with abdominal pain, profuse diarrhoea, lethargy and confusion. She was drowsy, hypotensive with a BP of 60/40 mmHg, hyponatraemic and hypoglycaemic. Thyroid function tests (TFTs) indicated profound hypothyroidism with a TSH of 19 mIU/L, and undetectable fT3 and fT4, despite the patient being compliant with thyroxine. She was diagnosed with a myxoedema coma caused by immune-related enteritis and subsequent thyroxine malabsorption. The patient was treated with i.v. triiodothyronine (T3) and methylprednisolone in the ICU. While her clinical status improved with T3 replacement, her enteritis was refractory to steroid therapy. A thyroxine absorption test confirmed persistent malabsorption. Attempts to revert to oral thyroxine were unsuccessful. Unfortunately, the patient’s malignant melanoma progressed significantly and she passed away four months later. This is the first reported case of myxoedema coma that resulted from two distinct immune-related adverse reactions, namely painless thyroiditis and enterocolitis. Learning points Myxoedema coma, a severe form of decompensated hypothyroidism is a rare immunotherapy-related endocrinopathy. Myxedema coma should be treated with either i.v. triiodothyronine (T3) or i.v. thyroxine (T4). Intravenous glucocorticoids should be co-administered with thyroid hormone replacement to avoid precipitating an adrenal crisis. Thyroid function tests (TFTs) should be monitored closely in individuals with hypothyroidism and diarrhoea due to the risk of thyroxine malabsorption. A thyroxine absorption test can be used to confirm thyroxine malabsorption in individuals with persistent hypothyroidism.

Summary Hyponatraemia is the most common electrolyte disturbance in hospitalised patients and is associated with numerous adverse outcomes. Patients with schizophrenia are particularly susceptible to hyponatraemia, in part due to the close association between this condition and primary polydipsia. We report the case of a 57-year-old woman with schizophrenia and primary polydipsia who was receiving inpatient psychiatric care. She became increasingly confused, had multiple episodes of vomiting, and collapsed 1 week after being commenced on quetiapine 300 mg. On examination, she was hypertensive and her Glasgow coma scale was nine. She had a fixed gaze palsy and a rigid, flexed posture. Investigations revealed extreme hyponatraemia with a serum sodium of 97 mmol/L. A CT brain demonstrated diffused cerebral oedema with sulcal and ventricular effacement. A urine sodium and serum osmolality were consistent with SIAD, which was stimulated by the introduction of quetiapine. The antidiuretic effect of vasopressin limited the kidney’s ability to excrete free water in response to the patients' excessive water intake, resulting in extreme, dilutional hyponatraemia. The patient was treated with two 100 mL boluses of hypertonic 3% saline but deteriorated further and required intubation. She had a complicated ICU course but went on to make a full neurological recovery. This is one of the lowest sodium levels attributed to primary polydipsia or second-generation antipsychotics reported in the literature. Learning points The combination of primary polydipsia and SIAD can lead to a life-threatening, extreme hyponatraemia. SIAD is an uncommon side effect of second-generation anti-psychotics. Serum sodium should be monitored in patients with primary polydipsia when commencing or adjusting psychotropic medications. Symptomatic hyponatraemia is a medical emergency that requires treatment with boluses of hypertonic 3% saline. A serum sodium of less than 105 mmol/L is associated with an increased risk of osmotic demyelination syndrome, therefore the correction should not exceed 8 mmol/L over 24 h.

Hyponatraemia is a common electrolyte abnormality seen in a wide range of oncological and haematological malignancies, and confers poorer performance status, prolonged hospital admission and reduced overall survival, in patients with cancer. Syndrome of inappropriate antidiuresis (SIAD) is the commonest cause of hyponatraemia in malignancy, and is characterised by clinical euvolaemia, low plasma osmolality, and concentrated urine, with normal renal, adrenal and thyroid function. Causes of SIAD include ectopic production of vasopressin (AVP) from an underlying tumour, cancer treatments, nausea and pain. Cortisol deficiency is an important differential in the assessment of hyponatraemia, as it has an identical biochemical pattern to SIAD, and is easily treatable. This is particularly relevant with the increasing use of immune checkpoint inhibitors, which can cause hypophysitis and adrenalitis, leading to cortisol deficiency. Guidelines on the management of acute, symptomatic hyponatraemia recommend 100ml bolus of 3% saline with careful monitoring of the serum sodium to prevent overcorrection. In cases of chronic hyponatraemia, fluid restriction is recommended as first line treatment, however this is frequently not feasible in patients with cancer and has been shown to have limited efficacy. Vasopressin-2 receptor antagonists (vaptans), may be preferable, as they effectively increase sodium levels in SIAD and do not require fluid restriction. Active management of hyponatraemia is increasingly recognised as an important component of oncological management; correction of hyponatraemia is associated with shorter hospital stay and prolonged survival. The awareness of the impact of hyponatraemia, and the positive benefits of active restoration of normonatraemia, remain challenging in oncology.