Diagnostics

• Focused clinical evaluation

  • Time of travel to regions where malaria is endemic and previous chemoprophylaxis

  • Evaluate for signs of severe malaria.

• Routine laboratory studies: CBC, CMP, LFTs, and coagulation panel to evaluate for organ dysfunction

• Parasitological testing: confirms the presence and determines the species of Plasmodia

  • Microscopic examination of thick and thin blood smears (gold standard) ]

  • Antigen detection test (more rapid but less sensitive)

• CBC: Changes in multiple parameters may occur.

  • Hemolytic anemia: ↓ Hb, ↓ haptoglobin, ↑ LDH, ↑ indirect bilirubin, ↑ reticulocytes

  • Thrombocytopenia

  • Leukocytosis or leukopenia are uncommon except in severe disease.

• Urinalysis: Hemoglobinuria may occur with intravascular hemolysis.

• Detects specific malaria antigens

• Allows for quick diagnosis if high‑quality microscopy is unavailable or delayed.

• Confirm all RDT results via microscopy when available.

Gold standard test: allows for visualization of parasites within RBCs via microscopy to confirm malaria diagnosis

• Thick blood smear: high sensitivity; best initial test

• Thin blood smear: lower sensitivity, high specificity; confirmatory test

  • Allows identification of Plasmodium species

  • Enables calculation of malaria parasitemia: the percentage of RBCs containing a Plasmodium organism; used to classify severity and monitor response to therapy.

  • Findings include:

    • Schuffner granules (fine, brick-red dots) within RBCs infected with P. vivax and P. ovale

    • Crescent-shaped gametocytes in individuals infected with P. falciparum

• Definition: symptomatic, diagnostically proven malaria without features of severe malaria Etiology: can be caused by all six Plasmodium species

• Description: potentially fatal manifestation or complication of malaria

• Etiology: most commonly a result of falciparum malaria

• Pathophysiology: Infected erythrocytes occlude capillaries, which can lead to severe organ dysfunction.

• Criteria for severe malaria: ≥ 1 of the following in a patient with proven malaria [16][19][21]

  • Clinical findings

    • General: prostration

    • CNS: hallucinations, confusion, impaired consciousness, seizures, coma

    • Cardiac: shock (e.g., hypotension, capillary refill time ≥ 3 seconds), heart failure

    • Pulmonary: respiratory distress, pulmonary edema, ARDS

    • Renal: flank pain, oliguria, hemoglobinuria, acute kidney injury

    • Gastrointestinal: jaundice

    • Hematopoietic: significant bleeding

  • Laboratory findings

    • Severe anemia: < 7 g/dL in adults, < 5 g/dL in children

    • Hypoglycemia: < 40 mg/dL

    • Acidosis (with or without lactemia): base deficit > 8 meq/L or bicarbonate < 15 meq/L

    • Hyperlactatemia: lactate > 5 meq/L

    • Acute kidney injury: creatinine > 3 mg/dL or urea > 20 mmol/L

    • Hyperbilirubinemia: bilirubin > 3 mg/dL

    • High malaria parasitemia