Table 2.
Characteristics of selected pulmonary infections in immunocompromised patients
| Organism | Associated Immune Disorders and Risk Factors | Clinical Presentation | Characteristics of Diagnosis |
|---|---|---|---|
| Aspergillus species, specifically A. fumigatus (fungus) | • Neutropenia | • Fever | • Imaging: ground-glass opacities; cavitary nodules present with invasive disease |
| • Hypo- or agammaglobulinemia | • Cough | • Serum testing: galactomannan; Aspergillus PCR | |
| • Immunosuppressive therapy | • Chest pain | • Bronchoscopy: tracheobronchitis with mucosal plaques and/or ulceration | |
| • BMT | • Throat pain | • BAL: fungal culture*; galactomannan: some studies show low sensitivity and possibility of cross-reactivity with other fungal infections; Aspergillus PCR: does not distinguish colonization from active infection | |
| • Invasive pulmonary disease (severe presentation) | • Biopsy of nodule/tissue: septate hyphae with acute branching pattern | ||
| • Elevated β-1-,3-d-glucan in serum and/or BAL | |||
| • Serum antigen testing | |||
| C. neoformans (fungus) | • HIV | • Cough | • Imaging: diffuse interstitial findings; pulmonary nodules |
| • Congenital T-cell disorders | • Fever | • BAL: India-ink stain reveals halo sign of polysaccharide capsule*; antigen testing | |
| • Immunosuppressive therapy | • Lymphadenopathy | • Low β-1,3-d-glucan in serum and/or BAL | |
| • Neurologic disease: headaches; meningismus | |||
| P. jirovecii (fungus) | • Hypo- or agammaglobulinemia | • Dyspnea | • Imaging: bilateral infiltrates; ground-glass or cystic lesions; nodules, with or without cavitation |
| • Congenital T-cell disorders | • Fever | • BAL or sputum: direct identification of organism*; tinctorial staining; fluorescent antibody staining; PCR | |
| • HIV | • Cough | • Elevated β-1,3-d-glucan levels in serum and/or BAL | |
| • Post-BMT | • Cyanosis (late) | ||
| • Immunosuppressive therapy | • Hypoxemic respiratory failure (late) | ||
| Candida species (fungus) | • Neutropenia | • Commonly presents with systemic findings due to hematogenous spread | • Imaging: microabscesses |
| • Congenital T-cell disorders | • White plaques on buccal mucosa | • Bronchoscopy: evidence of oropharyngeal plaques | |
| • Post-BMT | • Blood culture | ||
| • Chronic illness | • BAL: Gram stain or potassium hydroxide preparation; budding yeasts with or without pseudohyphae | ||
| • Elevated β-1,3-d-glucan (Fungitell) levels in serum and/or BAL | |||
| CMV (virus) | • Post-BMT | • Fever | • BAL: histopathology “owl-eye” inclusions or positive CMV-specific immunohistochemistry*; quantitative PCR; positive culture result |
| • HIV | • Malaise | • Serum: quantitative viral load; whole-blood PCR | |
| • Neonates | • Cough | ||
| • Other organ symptoms: retinitis; encephalitis; colitis | |||
| L. monocytogenes (bacteria) | • Neonates | • Fevers | • Radiology: ground-glass opacities |
| • HIV | • Chills | • Serum and CSF: Gram stain and culture*; PCR* | |
| • Post-BMT status | • Can present initially with septicemia | • BAL usually low-yield | |
| • Chronic gastrointestinal disease | • Neurologic symptoms: meningismus; seizures; cranial nerve abnormalities; encephalitis |
Definition of abbreviations: A. fumigatus = Aspergillus fumigatus; BAL = bronchoalveolar lavage; BMT = bone marrow transplantation; C. neoformans = Cryptococcus neoformans; CMV = cytomegalovirus; CSF = cerebrospinal fluid; HIV = human immunodeficiency virus; L. monocytogenes = Listeria monocytogenes; P. jirovecii = Pneumocystis jirovecii; PCR = polymerase chain reaction.
*
Gold standard.