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Nocardiosis

Last reviewed: 10 Apr 2025
Last updated: 21 Nov 2023

Summary

Definition

History and exam

Key diagnostic factors

  • cough with purulent sputum
  • fever
Full details

Other diagnostic factors

  • headache
  • nausea and vomiting
  • confusion
  • depressed consciousness
  • cutaneous ulcers or abscesses
Full details

Risk factors

  • solid organ and hematopoietic stem cell transplant recipients
  • HIV-positive and low CD4 T-cell count (<100 cells/mm³)
  • immunosuppression
  • structural pulmonary disease
  • malignancy and chemotherapy
  • agricultural work
Full details

Diagnostic tests

1st tests to order

  • Gram and acid-fast stains
  • culture
  • matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)
  • biochemical species typing
  • polymerase chain reaction (PCR)-based techniques
  • chest x-ray
  • CT head
Full details

Tests to consider

  • thoracic CT scan
  • MRI head
Full details

Emerging tests

  • next-generation sequencing

Treatment algorithm

ACUTE

severe nocardiosis: disseminated disease, CNS involvement, cavitary pulmonary lesions, or immunocompromise

nonsevere nocardiosis: immunocompetent, nondisseminated, no CNS involvement, no pulmonary cavitary lesions

Contributors

Authors

Timothy Sullivan, MD

Associate Professor

Division of Infectious Diseases

Icahn School of Medicine at Mount Sinai

New York

NY

Disclosures

TS declares that he has no competing interests.

Acknowledgements

Dr Timothy Sullivan would like to gratefully acknowledge Dr Jorge Garbino and Dr Juan Ambrosioni, previous contributors to this topic.

Disclosures

JG declares that he has no competing interests. JA is an advisory board member of Gilead Sciences and ViiV Healthcare.

Peer reviewers

Senu Apewokin, MD

Associate Professor of Medicine

Director, Transplant Infectious Diseases

University of Cincinnati

Cincinnati

OH

Disclosures

SA declares that she has no competing interests.

Rebecca N. Kumar, MD, MS

Assistant Professor of Medicine

Georgetown University Medical Center

Washington

DC

Disclosures

RNK has received research grants from Regeneron and Gilead, which have been paid to Georgetown University.

References

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Key articles

Brown-Elliott BA, Brown JM, Conville PS, et al. Clinical and laboratory features of the Nocardia spp. based on current molecular taxonomy. Clin Microbiol Rev. 2006 Apr;19(2):259-82.Full text  Abstract

Hamdi AM, Fida M, Deml SM, et al. Retrospective analysis of antimicrobial susceptibility profiles of Nocardia species from a tertiary hospital and reference laboratory, 2011 to 2017. Antimicrob Agents Chemother. 2020 Feb 21;64(3):e01868-19.Full text  Abstract

Corti ME, Villafane-Fioti MF. Nocardiosis: a review. Int J Infect Dis. 2003 Dec;7(4):243-50.Full text  Abstract

Margalit I, Lebeaux D, Tishler O, et al. How do I manage nocardiosis? Clin Microbiol Infect. 2021 Apr;27(4):550-8.Full text  Abstract

Restrepo A, Clark NM, Infectious Diseases Community of Practice of the American Society of Transplantation. Nocardia infections in solid organ transplantation: guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation. Clin Transplant. 2019 Sep;33(9):e13509. Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

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