Epidemiology

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Etiology

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• Pathogen: Nocardia species (ubiquitous in soil worldwide)
  • Reservoir: soil
  • Gram positive with branching filaments
  • Aerobe
  • Weakly acid-fast staining (Ziehl-Neelsen stain)
  • Catalase positive
• Risk factors
  • Immunocompromise (e.g., due to HIV infection, organ transplant, glucocorticoid therapy, recent chemotherapy, diabetes mellitus)

Pathophysiology

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Clinical features

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Pulmonary nocardiosis

• Risk group: immunocompromised individuals
• Clinical features
  • Constitutional: fever, weight loss, anorexia, night sweats
  • Respiratory (recurrent pneumonia): productive cough, dyspnea, pleuritic chest pain
  • Pulmonary nocardiosis symptoms such as fever, chills, and weight loss are often mistaken for tuberculosis

Diagnostics

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Treatment

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