1st order laboratory parameters – obligatory laboratory tests.
- Microscopic examination of the thick drop and thin blood smears (plasmodia direct detection) [gold standard] Specimen material should be collected at fever peak. Creating a “thick drop” (capillary blood); the “thick drop” is particularly suitable for sparse parasitemia (presence of parasites in the blood), as this leads to the accumulation of pathogens.
- Small blood count [thrombocytopenia/deficiency of platelets (blood platelets) in the blood]
- Differential blood count
- Inflammatory parameter – CRP (C-reactive protein)
- Urine status (rapid test for: pH, leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin, blood), sediment, if necessary urine culture (pathogen detection and resistogram, that is, testing suitable antibiotics for sensitivity / resistance).
- Fasting glucose (fasting blood glucose).
- Liver parameters – alanine aminotransferase (ALT, GPT), aspartate aminotransferase (AST, GOT), glutamate dehydrogenase (GLDH) and gamma-glutamyl transferase (γ-GT, gamma-GT; GGT).
- Renal parameters – urea, creatinine, cystatin C or creatinine clearance, as appropriate.
- Hemolysis signs – values such as LDH ↑ (lactate dehydrogenase), HBDH ↑ (hydroxybutyrate dehydrogenase), reticulocytes ↑, haptoglobin ↓ and indirect bilirubin ↑, indicating hemolysis (dissolution of red blood cells).
In case of clinical suspicion but negative microscopic findings, this examination must be repeated:
- Antigen detection by rapid malaria tests – cannot replace microscopic examination, as less sensitive! Should only be used if microscopic pathogen detection is not available.
- Malaria PCR – only applicable in special cases ( e.g. parasite detection in organ samples in the context of a forensic investigation); unsuitable for acute diagnostics because it takes a comparatively long time (several hours) and is very costly; real-time PCR is usually not available.
- Serological tests are useless in acute cases
Direct or indirect detection of “Plasmodium sp.” is reportable under the Infection Protection Act (IfSG).
Laboratory parameters 2nd order – depending on the results of the history, physical examination, etc. – if malaria diagnostics are negative.
- Blood, stool and urine cultures – especially to exclude typhoid abdominalis.
- For further diagnostics, see under fever/laboratory diagnostics – see there under “Fever after a stay in the tropics or subtropics”
