OA28 Really... gout?! An unexpected diagnosis of gout in the wrist of a 12-year-old girl

Abstract Introduction Gout is a common form of inflammatory arthritis in adults but is rare in children and adolescents. Few studies have examined paediatric gout. There are no treatment pathways for the disease. The term gout refers to a collection of disorders characterised by an elevated level of uric acid in the blood, leading to the deposition of monosodium urate crystals within joints. Hyperuricemia can occur due to increased production of uric acid or decreased renal excretion of uric acid. Gout is a chronic erosive arthritis associated with subcutaneous periarticular deposits of urate or tophi and nephrocalcinosis. Case description A 12-year-old girl presented with soft tissue swelling and tenderness of the left wrist during a hospital admission for a methicillin-sensitive Staphylococcus aureus (MSSA) line infection in September 2024. Her complex medical history included 1p36 deletion syndrome, global developmental delay, chronic intestinal failure, jejunostomy in situ, and dependence on parenteral nutrition (PN). MRI left wrist in September 2024 suggested an inflammatory or infectious tenosynovitis with reactive osteomyelitis, likely secondary to MSSA bacteraemia. She completed a prolonged course of intravenous antibiotics. On outpatient review in December 2024, both clinical and radiological signs of osteomyelitis had resolved. The patient is non-verbal; therefore, a lot of the history relied on her mother in particular. This patient’s mother reported that she was always concerned about an ongoing level of pain that this young girl was experiencing, though it was unclear where the location of this could be. In May 2025, this young girl developed acute swelling over the dorsal aspect of the left hand. Ultrasound of the swelling showed a 9x6 mm cyst, suggestive of a ganglion. In June 2025, she was admitted with fever and pallor. Examination showed erythema, swelling, and tenderness over the dorsum of the left hand, with reduced wrist range of motion. Inflammatory markers were elevated (CRP 346, ESR 119). She was started on IV antibiotics for presumed osteomyelitis. MRI findings were again suggestive of infectious tenosynovitis. Given that this was a second presentation of infectious tenosynovitis with associated osteomyelitis in the same location, a surgical washout and biopsy was organised with the plastic surgical team. Surgical exploration and washout revealed haemopurulent discharge with areas of tophaceous calcification as well as calcified tophi extending to the wrist joint. Laboratory analysis of samples confirmed the presence of solid monosodium urate crystals, consistent with a diagnosis of gout. Notably, serum uric acid levels were within the normal range. She was started on colchicine with good clinical response. A six week course of antibiotics were also completed, given the haemopurulent discharge in theatre and concerns about osteomyleitis. At the last clinical review, this patient is on colchicine alone. Discussion Gout is extremely rare in the paediatric population. Gout results after prolonged hyperuricaemia. It occurs from the increased production or decreased excretion of uric acid. Clinical features of gout include pain, swelling, redness and heat within the affected joint. A decreased range of movement may be felt on examination. There may be an accompanying fever. The first metatarsophalangeal joint is most commonly affected, with joints of the lower limbs typically involved more frequently than those of the upper limbs. When gout does occur, it is often associated with underlying medical conditions. Causes due to increased uric acid production include Lesch Nyhann syndrome, Becker syndrome, myelproliferative disorders, Gaucher disease, cytotoxic drugs and chronic hemolysis. Causes due to decreased uric acid excretion include reduced glomerular filtration rate, Down syndrome, amyloidosis, sarcoidosis, hypothyroidism, diuretics, type 1 glycogen storage disease, and increased levels of organic acids. In this case, the patient was dependent on parenteral nutrition, which has been associated with transient hypouricemia followed by rapid increases in uric acid levels, potentially triggering gout flares. Medications may have contributed. Among her medications, clonidine is known to increase uric acid levels, while deoxycholic acid may reduce them. Therefore, the net effect of these medications on uric acid metabolism remains unclear. The diagnosis of gout confirmed by identifying monosodium urate crystals in synovial fluid or tophi aspirate. Ultrasound is the best modality to detect asymptotic tophi. This is widely used in adult medicine. MRI can also be used. Treatment of the acute attack tends to be with NSAIDs or colchicine. Short-term corticosteroids may be considered, as can intra-articular corticosteroid injections. After the acute attack has resolved, allopurinol can be considered; however, the uric acid level in the bloods should be taken into account. Key learning points Gout, although rare in children, should be considered in cases of persistent joint swelling, especially in those with complex medical backgrounds. In these cases, joint aspiration, synovial biopsies and crystal analysis should be considered to look for rarer causes of joint pain and swelling, such as gout. Parenteral nutrition and medications can alter uric acid metabolism and predispose individuals to crystal arthropathies. This should be considered in children and young people with more complex medical conditions. Normal serum uric acid levels do not exclude the diagnosis of gout. As always in rheumatology, think about and exclude infection whilst searching for inflammatory causes of arthritis. Gout remains a challenging diagnosis to make in children and young people, but nonetheless should be considered in those with inflamed joints are not felt to be a typical juvenile idiopathic arthritis.