Moeller Karen E, Touma Susan C
Department of Pharmacy Practice, The University of Kansas Medical Center, Kansas City, KS 66160-7231, USA.
Ann Pharmacother. 2003 Nov;37(11):1622-4. doi: 10.1345/aph.1D098.
To report a case of severe prolonged thrombocytopenia possibly associated with isotretinoin.
A 27-year-old white woman developed severe thrombocytopenia and elevated transaminases after 3(1/2) months of treatment with isotretinoin. Prior to the onset of thrombocytopenia, the patient had also received a 10-day course of cephalexin. Rectal bleeding was reported by the patient, who was otherwise asymptomatic. Liver enzyme values returned to normal approximately 1 week after discontinuation of isotretinoin; however, platelet counts required approximately 2 months to normalize. Based on the Naranjo probability scale, possible causality exists between isotretinoin and thrombocytopenia.
The exact mechanism by which isotretinoin caused thrombocytopenia in this patient is not clearly understood. To our knowledge, only 3 previous cases of isotretinoin-associated thrombocytopenia have been reported. The long recovery process that occurred in our patient is possibly a direct result of the long elimination half-life of both the parent compound and active metabolites of isotretinoin.
Clinicians prescribing isotretinoin should be aware of the potential life-threatening consequence of thrombocytopenia, and a complete blood cell count with platelets should be part of the routine monthly monitoring in all patients receiving isotretinoin therapy.
报告一例可能与异维A酸相关的严重持续性血小板减少症病例。
一名27岁白人女性在接受异维A酸治疗3个半月后出现严重血小板减少和转氨酶升高。在血小板减少症发作之前，患者还接受了为期10天的头孢氨苄治疗。患者报告有直肠出血，除此之外无其他症状。停用异维A酸后约1周，肝酶值恢复正常；然而，血小板计数大约需要2个月才能恢复正常。根据Naranjo概率量表，异维A酸与血小板减少症之间可能存在因果关系。
异维A酸导致该患者血小板减少的确切机制尚不清楚。据我们所知，此前仅报道过3例与异维A酸相关的血小板减少症病例。我们的患者出现的漫长恢复过程可能是异维A酸母体化合物及其活性代谢物消除半衰期较长的直接结果。
开具异维A酸处方的临床医生应意识到血小板减少症可能危及生命的后果，对于所有接受异维A酸治疗的患者，常规每月监测应包括血小板全血细胞计数。
