{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T14:51:22Z","timestamp":1782399082586,"version":"3.54.5"},"reference-count":34,"publisher":"BMJ","issue":"6","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2026,3,16]]},"published-print":{"date-parts":[[2026,6]]},"abstract":"<jats:p>\n                    A female patient diagnosed with an undifferentiated connective tissue disorder (UCTD) experienced progressive symptoms including hair loss, vomiting, diarrhoea and abdominal pain accompanied by haematological changes of anaemia, absolute neutropenia with thrombocytosis following 7\u2009weeks of azathioprine therapy. Consequently, azathioprine was discontinued, resulted in hematologic recovery and hair regrowth. Genetic analysis revealed the presence of an\n                    <jats:italic>NUDT15<\/jats:italic>\n                    polymorphism, indicating impaired thiopurine metabolism. Hair loss was the first symptom, above all others, indicating an early onset of anagen effluvium as a warning sign of myelotoxicity. The reactive thrombocytosis was attributed to cytokine-mediated inflammation involving IL-1 and IL-6, suggesting a combined haematological response to azathioprine. It is recommended that Clinicians perform a preliminary genetic testing to prevent the need for frequent blood monitoring and to avoid myelotoxicity\n                  <\/jats:p>","DOI":"10.1136\/bcr-2025-269387","type":"journal-article","created":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T14:25:22Z","timestamp":1782397522000},"page":"e269387","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Thrombocytosis in a patient with\n                    <i>NUDT15<\/i>\n                    homozygous variant: clues in clinical pharmacogenetics"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-5401-3511","authenticated-orcid":false,"given":"Sabbariventhansastha","family":"Pandian","sequence":"first","affiliation":[{"name":"Pharmacology, All India Institute of Medical Sciences Kalyani, Kalyani, West Bengal, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ritasman","family":"Baisya","sequence":"additional","affiliation":[{"name":"Rheumatology & Clinical Immunology, All India Institute of Medical Sciences Kalyani, Kalyani, West Bengal, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8523-736X","authenticated-orcid":false,"given":"Sukdev","family":"Manna","sequence":"additional","affiliation":[{"name":"Rheumatology & Clinical Immunology, All India Institute of Medical Sciences Kalyani, Kalyani, West Bengal, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5832-4580","authenticated-orcid":false,"given":"Soumitra","family":"Mandal","sequence":"additional","affiliation":[{"name":"Pharmacology, All India Institute of Medical Sciences Kalyani, Kalyani, West Bengal, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"key":"2026062507251071000_19.6.e269387.1","doi-asserted-by":"crossref","DOI":"10.1186\/s12876-023-02881-6","article-title":"Analysis of the NUDT15 gene and metabolites of azathioprine in Japanese patients with inflammatory bowel disease","volume":"23","author":"Suzuki","year":"2023","journal-title":"BMC Gastroenterol"},{"key":"2026062507251071000_19.6.e269387.2","doi-asserted-by":"publisher","DOI":"10.1093\/ECCO-JCC\/JJAB178"},{"key":"2026062507251071000_19.6.e269387.3","doi-asserted-by":"publisher","DOI":"10.1053\/j.gastro.2021.04.022"},{"key":"2026062507251071000_19.6.e269387.4","doi-asserted-by":"publisher","DOI":"10.1053\/j.gastro.2020.01.006"},{"key":"2026062507251071000_19.6.e269387.5","doi-asserted-by":"crossref","unstructured":"Lamb CA , Kennedy NA , Raine T , et al . 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