PT  - JOURNAL ARTICLE
AU  - Axel Steppat
AU  - Nanna Skaarup Andersen
AU  - Caroline Marie Andreasen
TI  - Rare case of Lyme borreliosis in a patient presenting with dactylitis and skin rash
AID  - 10.1136/bcr-2022-253182
DP  - 2023 Feb 01
TA  - BMJ Case Reports
PG  - e253182
VI  - 16
IP  - 2
4099  - http://casereports.bmj.com/content/16/2/e253182.short
4100  - http://casereports.bmj.com/content/16/2/e253182.full
SO  - BMJ Case Reports2023 Feb 01; 16
AB  - An immunocompetent male in his 70s was diagnosed with psoriatic arthritis based on dactylitis, onycholysis of the nails and scalp psoriasis. He was treated with corticosteroids, methotrexate and local corticosteroid injections without improvements in his symptoms. When tumor necrosis factor-alpha inhibitor treatment was introduced, the symptoms worsened and dactylitis of all digits and a bluish-red rash were observed on the extensor side of the left hand and arm. At this point, a skin biopsy was performed showing histopathological changes compatible with Lyme borreliosis and serum contained IgG antibodies against Borrelia burgdorferi. It was concluded that he was suffering from acrodermatitis chronica atrophicans (ACA) and Lyme dactylitis. Ten days of phenoxymethylpenicillin treatment was initiated, and after 2 weeks, the dactylitis and ACA had regressed substantially. After 6 months, both had resolved. This case emphasises the need for clinical reassessment, when treatment is not effective.