TABLE 2.2.
Histochemical Staining Characteristics of Microbes
| Organism | Staining Characteristics |
|---|---|
| Viruses | |
| Influenza | No cytopathic change |
| Coronavirus (SARS) | No cytopathic change |
| Adenovirus | H&E (smudge cells); IHC |
| Cytomegalovirus | H&E (intranuclear and cytoplasmic inclusions); IHC; PAS and GMS (intracytoplasmic inclusions) |
| Herpes virus | H&E (intranuclear inclusions); IHC |
| Measles | H&E (intranuclear inclusions, polykaryons) |
| Respiratory syncytial virus | H&E (polykaryons); IHC |
| Parainfluenza | H&E (intracytoplasmic inclusions) |
| Bacteria | |
| Gram positive | Tissue Gram, GMS (all) |
| Gram negative | Tissue Gram, GMS (some) |
| Legionella | Silver impregnation |
| Nocardia | Tissue Gram, GMS, modified ZN |
| Actinomyces | Tissue Gram, GMS |
| Mycobacteria tuberculosis | ZN and modified ZN; PCR |
| Atypical mycobacteria | Mo dified ZN, ± ZN, PCR |
| Fungi | |
| Histoplasma | GMS, PAS |
| Cryptococcus | H&E, GMS, PAS, mucicarmine; Fontana, IHC |
| Blastomyces | H&E, GMS, PAS, mucicarmine (weak) |
| Coccidiomyces | H&E, GMS, PAS |
| Candida | H&E, GMS, PAS, Gram stain; IHC |
| Aspergillus | H&E, GMS, PAS, IHC |
| Zygomyces | H&E, GMS, PAS |
| Pseudeallescheria | H&E, GMS, PAS |
| Alternaria and dematiaceous fungi | H&E, GMS, PAS, Fontana |
| Parasites | |
| Protozoa | H&E, PAS, Gram stain (microsporidia); IHC (Toxoplasma) |
| Metazoans | H&E, trichrome stain |
| Echinococcus | GMS in chitinous wall, modified ZN (hooklets) |
| Paragonimiasis | Ova birefringent |
| Schistosomiasis | Lateral and terminal spines stain with modified ZN |
GMS, Gomori methenamine silver stain; H&E, hematoxylin and eosin stain; IHC, immunohistochemical methods; PAS, periodic acid–Schiff stain; PCR, polymerase chain reaction; SARS, severe acute respiratory syndrome; ZN, Ziehl-Neelsen stain.