1st order laboratory parameters – obligatory laboratory tests.
- Microscopic pathogen detection of cysts or trophozoites in stool: from bloody-mucous portions of fresh stool. Note: Only magnaforms (trophozoites that have phagocytosed erythrocytes (red blood cells); subsequent enzymatic degradation of erythrocytes) with amebic movement prove amebiasis! If minutaforms (trophozoites that have not phagocytosed erythrocytes) are detected in the stool, the diagnosis is not confirmed. It may be a harmless concomitant infection with the apathogenic (without pathological significance) E. dispar.
- Serology: combination of at least two different antibody detections:
- ELISA (Enzyme Linked Immunosorbent Assay),
- IFAT (Immuno Fluorescent Antibody Test),
- IHA (Indirect Hemagglutination).
- Pathogen detection by PCR (polymerase chain reaction; is superior to other diagnostic methods) – Detection of E. histolytica DNA allows species differentiation:
- E. dispar – apathogenic
- E. histolytica sensu stricto – actual pathogen.
- Inflammatory parameters as a progression parameter – CRP (C-reactive protein) or PCT (procalcitonin) or ESR (erythrocyte sedimentation rate).
- Electrolytes in severe diarrhea – calcium, chloride, potassium, magnesium, sodium, phosphate.
- Liver parameters – alanine aminotransferase (ALT, GPT), aspartate aminotransferase (AST, GOT), glutamate dehydrogenase (GLDH) and gamma-glutamyl transferase (gamma-GT, GGT), alkaline phosphatase, bilirubin [transaminase enzymes elevated?; cholestasis enzymes elevated?]
- Small blood count
- Differential blood count
- Stool examination for enteropathogenic pathogens (e.g., Escherichia coli, Salmonella, Shigella, Campylobacter) if:
- Appearance of diarrhea symptoms shortly after returning from a stay abroad.
- Symptomatology not improved even after seven days
- Doubts about the diagnosis of gastroenteritis (stomach flu) exist
