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Human polyomavirus 9 infection
Other Resources UpToDate PubMed

Human polyomavirus 9 infection

Contributors: Asha Nanda MD, Jourdan Brandon MD, Susan Burgin MD
Other Resources UpToDate PubMed


Human polyomavirus 9 (HPyV9) is a polyomavirus with up to 30% seroprevalence in solid organ transplant recipients (SOTRs). Despite its significant seroprevalence in this population, it had previously not been associated with disease. However, in 2022, sentinel literature described a hyperkeratotic papular eruption followed by pulmonary compromise, clinical decline, and death in SOTRs from HPyV9 infection. Patients were 7-13 years out from their transplants (kidneys or lung), and 2 of the 3 had a history of more than 1 transplant (3 kidney transplants in 1 patient and 2 lung transplants in another). Each patient developed an acral eruption that generalized and was followed by the development of systemic symptoms, including anorexia, weight loss, fatigue, dyspnea, and ultimate demise 4-13 months after rash onset. Acute lung injury from diffuse alveolar hemorrhage was thought to be the cause of death in the reported patients.


B33.8 – Other specified viral diseases

5714002 – Disease caused by Polyomavirus

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Differential Diagnosis & Pitfalls

  • Cytomegalovirus infection – Timing of onset is typically 4-6 weeks posttransplant rather than years after transplant.
  • Herpes zoster or Herpes simplex virus reactivation – Characteristic painful lesions are distinct from the hyperkeratotic lesions observed in HPyV9 infection.
  • Pneumocystis jirovecii pneumonia – This diagnosis is established with bronchoalveolar lavage (BAL).
  • Cutaneous lymphoproliferative disorders (eg, Epstein-Barr virus infection)
  • Disseminated fungal infections (eg, Candidiasis, Cryptococcosis, Histoplasmosis) – Diagnosis is established with urine culture or cerebrospinal fluid culture.
  • Pruritic and dyskeratotic dermatosis
  • Lichen planus
  • Acquired perforating disease
  • Eruptive keratoacanthomas
  • Trichodysplasia spinulosa
  • Lichenoid drug eruption
  • Acrokeratosis paraneoplastica

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Last Reviewed:06/21/2022
Last Updated:06/22/2022
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Human polyomavirus 9 infection
A medical illustration showing key findings of Human polyomavirus 9 infection : Acral distribution, Malaise, Anorexia, Dyspnea
Copyright © 2024 VisualDx®. All rights reserved.