Lithium is a mood stabiliser widely used in the treatment and prophylaxis of mania, bipolar disorders and recurrent depression. Treatment with lithium can give rise to various endocrine and metabolic abnormalities, including thyroid dysfunction, nephrogenic diabetes insipidus and hypercalcaemia. Lithium may induce hypercalcaemia through both acute and chronic effects. The initial acute effects are potentially reversible and occur as a result of lithium's action on the calcium-sensing receptor pathway and glycogen synthase kinase 3, giving rise to a biochemical picture similar to that seen in familial hypocalciuric hypercalcaemia. In the long term, chronic lithium therapy leads to permanent changes within the parathyroid glands by either unmasking hyperparathyroidism in patients with a subclinical parathyroid adenoma or possibly by initiating multiglandular hyperparathyroidism. The latter biochemical picture is identical to that of primary hyperparathyroidism. Lithium-associated hyperparathyroidism, especially in patients on chronic lithium therapy, is associated with increased morbidity. Hence, regular monitoring of calcium levels in patients on lithium therapy is of paramount importance as early recognition of lithium-associated hyperparathyroidism can improve outcomes. This review focuses on the definition, pathophysiology, presentation, investigations and management of lithium-associated hyperparathyroidism.

No abstract

No abstract

No abstract

Spontaneous pneumomediastinum is the presence of free air around mediastinal structures and frequently associated with other forms of extra-alveolar air, such as pneumopericardium, and pneumothorax. It is an uncommon occurrence and typically presents with pleuritic chest discomfort, dyspnea, odynophagia, and neck pain. It is frequently seen following chest trauma or in patients with underlying lung or connective tissue disorders. COVID-19 infection has been linked to spontaneous pneumomediastinum. We present two case reports of pneumomediastinum in two male patients whilst being treated for COVID-19 pneumonia. In one case, the pneumomediastinum was completely spontaneous whilst in the second case it was likely secondary to high flow nasal oxygen therapy. In both cases, patients were treated conservatively, and follow-up chest imaging showed complete resolution. One should keep in mind the possibility of such complication and have a low threshold for chest imaging in patients failing to improve or have sudden deterioration.