Holt-Oram syndrome is a rare autosomal dominant disorder which occurs because of mutations in the TBX5 genes. Most notable manifestations include musculoskeletal deformities, predominantly affecting the upper limbs, and congenital heart defects. Presentation could be multifaceted leading to delay in diagnosis. We describe an interesting incidental diagnosis of Holt-Oram syndrome in a young female adult who accompanied her son to the clinic. He had undergone closure of both atrial septal defect (ASD) and patent ductus arteriosus (PDA) in his infancy. She reported progressive exertional dyspnoea, reduced exercise tolerance, and palpitations; incidentally, she was noted to have right upper limb deformities. These findings prompted further evaluation and thereafter, resulted in a diagnosis of Holt-Oram syndrome.

Thyrotoxic hypokalaemic periodic paralysis (THPP) is a rare complication of hyperthyroidism that is potentially life-threatening if not treated promptly. It is more common in Asian and Polynesian populations and very few cases have been reported to date in people of White ethnicity. We present a case report of a young male patient of White ethnicity, who was initially brought in as a stroke alert with tetraparesis which was ruled out on initial assessment, but then had a syncopal episode and was noted to be initially bradycardic and subsequently tachycardic. Blood tests showed hypokalaemia and hypophosphataemia and he was treated as a hypokalaemic periodic paralysis patient. Intravenous potassium replacement was commenced. Symptoms and ECG changes resolved with correction of potassium levels. Thyroid function tests requested later were suggestive of hyperthyroidism and the diagnosis of thyrotoxic hypokalaemic periodic paralysis was made. This is an interesting case given its rarity, and this case report highlights the importance of early diagnosis and prompt treatment.