From the Guidelines
Malaria typically presents with a classic triad of symptoms: fever, chills, and sweating, often occurring in cyclical patterns, and can rapidly progress to severe complications if not promptly diagnosed and treated. The clinical features of malaria can vary depending on the Plasmodium species involved, but common initial symptoms include headache, fatigue, muscle aches, and nausea, which may be mistaken for a viral illness 1. The hallmark paroxysms of malaria involve sudden high fever (often exceeding 40°C), followed by intense shivering and chills, then profuse sweating as the fever breaks. These cycles typically occur every 48-72 hours depending on the Plasmodium species involved. Severe malaria, particularly from P. falciparum, can rapidly progress to complications including cerebral malaria (confusion, seizures, coma), severe anemia, respiratory distress, acute kidney injury, hypoglycemia, and metabolic acidosis 1.
Clinical Features of Severe Malaria
Severe malaria is a life-threatening condition that requires prompt medical attention. According to the WHO epidemiological and research criteria, severe malaria is characterized by:
- Impaired consciousness, Glasgow Coma scale score <11, or multiple convulsions (>2 seizures within 24 hours)
- Severe anemia (haemoglobin concentration <7 g/dL or haematocrit <20% with a parasite count >10,000/mL)
- Hypoglycemia (blood glucose <40 mg/dL or 2.2 mmol/L)
- Metabolic acidosis (pH <7.35 or plasma bicarbonate <15 mmol/L) or hyperlactataemia (venous plasma lactate >5 mmol/L)
- Parasitaemia >5% (non-immune subjects), >10% (semi-immune subjects) 1
Laboratory and Radiology Findings
Laboratory findings often show thrombocytopenia, anemia, elevated liver enzymes, and hyperbilirubinemia. Radiologically confirmed pulmonary oedema or acute respiratory distress syndrome (ARDS) can also occur. The periodicity of fever patterns can help identify the infecting species: P. falciparum and P. vivax typically cause fevers every 48 hours, while P. malariae causes fevers every 72 hours 1.
Importance of Early Recognition and Treatment
Early recognition of these clinical features is crucial for prompt diagnosis and treatment to prevent progression to severe disease and death. Intravenous artesunate is the recommended first-line treatment for all forms of severe malaria, and it is essential to manage clinical complications of severe malaria according to guidelines and recent achievements 1.
From the Research
Clinical Features of Malaria
The clinical features of malaria are diverse and can range in severity from mild to severe. Some of the common symptoms include:
- Fever, which is the cardinal feature of malaria 2
- Malaise
- Headache
- Myalgias
- Jaundice
- Gastrointestinal symptoms such as nausea, vomiting, and diarrhea 2
- Respiratory distress, which can develop in up to 25% of adults and 40% of children with severe falciparum malaria 3
Severe Malaria
Severe malaria is a life-threatening but treatable disease, mainly caused by Plasmodium falciparum 4, 2. It can lead to serious complications, including:
- Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) 3
- Noncardiogenic pulmonary edema
- Concomitant pneumonia
- Severe anemia
- Metabolic acidosis
- Cerebral malaria, which can cause increased intracranial pressure and cerebral swelling 3
High-Risk Groups
Certain groups are at higher risk of severe malaria, including:
- Children, especially those under the age of five 4, 5
- Pregnant women, who are at increased risk of developing ARDS 3
- People who are not from endemic regions, who may have little or no immunity to the disease 6, 4
Diagnosis and Treatment
Prompt diagnosis and appropriate treatment are crucial to prevent morbidity and fatal outcomes. The diagnosis of malaria is typically made by microscopic examination of blood films 2, and treatment is usually with artemisinin-based combination therapies 6, 4, 5. In severe cases, intravenous artesunate is the treatment of choice 4, 3.