Table 4.
Diagnostic tests for oncology patients with possible pneumonia
| Initial laboratory testing | Additional baseline laboratory tests to consider |
| CBC with manual differential | Nasal or naspopharyngeal specimen for extended viral testing for human metapneumovirus, adenovirus, rhinovirus, parainfluenzavirus |
| Comprehensive metabolic panel | Sputum fungal stain and culture |
| Blood cultures | Sputum AFB stain and mycobacterial culture |
| Minimum of 2, more if endocarditis is suspected | Urinary Histoplasma antigen |
| Urinalysis and urine culture | Urinary Blastomyces antigen |
| Chest XRAY (PA and lateral views) | Urinary Coccidioides antigen |
| Sputum culture for bacterial culture | Fungal serologies (lower yield than urinary antigens) |
| Useful specimen if >25 WBC/hpf and <10 epithelial cells/hpf observed | Serum cryptocococcal antigen |
| Nasal or nasopharyngeal specimen for viral PCR testing (for influenza and RSV) | Strongyloides serology and stool examination for ova and parasites |
| Streptococcus pneumoniae urinary antigen | |
| Legionella urinary antigen (serogroup 1) | |
| Aspergillus galactomannan assay | |
| CMV pp65 or CMV PCR from blooda | |
| If bronchoalveolar lavage or lung tissue is obtained | If pleural fluid is obtained |
| Gram stain and quantitative bacterial culture | pHc |
| Legionella DFA and culture | LDHc |
| KOH stain and fungal culture | Proteinc |
| AFB stain and mycobacterial culture | Glucosec |
| Viral culture (rapid shell vial culture) or | Cell count with differential |
| Extended viral PCR testing | Gram stain with quantitative bacterial culture |
| PCP DFA assay | KOH stain and fungal culture |
| Aspergillus galactomannan assay | AFB stain and mycobacterial culture |
| 16S ribosomal RNA sequencingb | Legionella DFA and culture |
| Cytology ± histology depending on specimen | PCP DFA assay |
| 16S ribosomal RNA sequencingb | |
| Cytology (+Histology if tissue obtained) | |
| Aspergillus galactomannan assay |
aSend in stem cell transplant recipients
bLimited availability, primarily a research tool
cDetermine whether pleural fluid is transudate or exudate
CBC complete blood count, PA posteroanterior, hpf high-power field, PCR polymerase chain reaction; RSV respiratory syncytial virus, DFA direct fluorescent antibody, KOH potassium hydroxide, AFB acid fast bacilli, PCP Pneumocystis jerovechi, and RNA ribonucleic acid