Respiratory infection in an immunocompromised person

From IDWiki

Differential Diagnosis

By Defect

Risk Factor Differential Diagnosis Investigations
Cell-Mediated Immunodeficiency
Steroids and solid organ transplantation opportunistic infections, systemic viruses, Pneumocystis, Cryptococcus, Mycobacteria, Toxoplasma sputum and blood culture, antigenuria, multiplex viral PCR, CMV/HSV/VZV PCR, bronchoalveolar lavage, Toxoplasma/Cryptococcus PCR, induced sputum, beta-D glucan
Hairy cell leukemia, acute T-cell leukemia, T-cell lymphoma
Fludarabine, ibrutinib, alemtuzumab
HIV
Humoural Immunodeficiency
Splenectomy and asplenism bacterial pneumonia (Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae) sputum and blood cultures, antigenuria, multiplex viral PCR
Complement deficiency
Common variable immunodeficiency
Rituximab and other anti-CD20 therapy
Multiple myeloma and CLL
Phagocyte Defects
Steroids and solid organ transplantation systemic viruses, Aspergillus, Mycobacteria, Nocardia, Mucorales, Toxoplasma sputum and blood cultures, antigenuria, multiplex viral PCR, CMV/HSV/VZV PCR, induced sputum, bronchoalveolar lavage, fungal culture of sputum, β-D glucan and galactomannan, Aspergillus PCR, Toxoplasma/Cryptococcus PCR
Neutropenia
Myelodysplastic syndrome
Acute myelogenous leukemia
Allogeneic hematopoietic stem cell transplantation

By CT Pattern

Pattern Differential Diagnosis Investigations
nodular lesions bacterial pneumonia, Aspergillus, Nocardia, Mucorales sputum and blood cultures, antigenuria, sputum with fungal culture, Aspergillus/Mucorales PCR, galactomannan and β-D glucan, bronchoalveolar lavage
septal thickening atypical bacterial pneumonia sputum and blood cultures, antigenuria, bronchoalveolar lavage
cavitations Mycobacteria, Histoplasma, bacterial pneumonia including Staphylococcus aureus sputum and blood cultures, mycobacterial culture, Histoplasma PCR
excavated nodules bacterial pneumonia, Mucorales, Nocardia, Actinomyces, Aspergillus sputum and blood cultures, Aspergillus/Nocardia/Mucorales PCR, galactomannan and β-D glucan
consolidation bacterial pneumonia, Aspergillus sputum and blood cultures, antigenuria, sputum for fungal culture, galactomannan and β-D glucan
pleural effusion bacterial pneumonia, tuberculosis sputum and blood cultures, antigenuria, mycobacterial blood culture, pleural aspiration and culture
ground glass opacities Pneumocystis, viral pneumonia, atypical bacterial pneumonia sputum and blood culture, Legionella antigenuria, sputum for Pneumocystis, β-D glucan, multiplex viral PCR, CMV/VZV/HSV blood PCR, bronchoalveolar lavage

Further Reading

  • Diagnosis of severe respiratory infections in immunocompromised patients. Intensive Care Med. 2020;46:298-314. doi: 10.1007/s00134-019-05906-5