Related Subjects:
|Fever in a traveller
|Malaria Falciparum
|Malaria Non Falciparum
|Viral Haemorrhagic Fevers (VHF)
|Lassa fever
|Dengue
|Marburg virus disease
|AIDS HIV
|Yellow fever
|Ebola Virus
|Leptospirosis
|Crimean-Congo haemorrhagic fever
|African Trypanosomiasis (Sleeping sickness)
|American Trypanosomiasis (Chagas Disease)
|Incubation Periods
|Notifiable Diseases UK
Always consider falciparum malaria in anyone with a flu-like illness recently in an endemic area in the past 3 months and speak to the lab and specialists and send thick and thin films. Take expert Tropical disease or Infectious diseases help early. A patient with a flu-like illness and Falciparum malaria can die before the post take ward round so it will be on the first contact to take a history and consider the diagnosis.
Initial Management Complicated Disease |
- History/Exam and Get Thick/Thin films or Antibody. ID consult
- ABC, Admit HDU. Monitor Blood glucose. Strict I/O monitoring
- IV Quinine 20 mg/kg (check QT first) loading dose OR
- IV Artesunate 2.4 mg/kg loading dose
- Transfuse anaemia and manage high fever. Ensure hydrated.
- Seizures: see Status Epilepticus
- Bacterial infection too: Antibiotics
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- Falciparum malaria can kill within hours and the presentation can be vague and it should be suspected in all coming from an endemic area within the past 3 months.
- Red cell involved >2% is severe
Anopheles female blood feeding and Plasmodium falciparum eggs in Anopheles mosquito midguts.
Aetiology
- Infection by a protozoan parasite found in tropics and subtropics
- Malaria in the UK is an imported disease but there is evidence that it was once indigenous
- Spread is from the female Anopheles mosquito or sometimes from infected blood or imported mosquitos e.g. near airports
- Rosetting is another finding where infected cells adhere to uninfected RBC's.
Cytoadherence
- Lethal form is plasmodium falciparum
- Mechanism is possibly through the process of cytoadherence
- Infected red cells adhere to the walls and block post capillary venules
- Formation of P. falciparum erythrocyte membrane protein (PfEMP)-1.
Epidemiology
- Kills 1 million humans year after year
- Mostly in Africa but also SE Asia and South America Amazon region
Steps
- Sporozoites enter via skin from feeding mosquito enter the liver and become merozoites
- Multiply in the liver and then hepatocyte ruptures releasing merozoites which enter RBCs
- Further steps until erythrocytes ruptures and/or adhere to vascular endothelium with organ damage brain, gut, liver, kidney
Clinical
- Flu like - malaise fever and headache, Rigors
- Severe cerebral malaria - coma, fits, paralysis - hemiparesis, blindness
- Mild hepatosplenomegaly may be found
Complications
- Reduced GCS and seizures and coma
- Acute renal failure: dialysis in 10%
- Metabolic acidosis
- Parasitaemia = 10%
- Hypoglycaemia
- Intravascular haemolysis, Jaundice
- Oliguria, Haemoglobinuria "Blackwater fever"
- DIC: D-Dimers, low platelets and FDP's elevated
- Non cardiogenic pulmonary oedema and ARDS
- Anaemia Hb =8g/dl
Investigations
- FBC, U&E, CRP, LFT, Glucose, Lactate
- Blood culture, Urine culture, Stool culture
- CXR: pneumonia
- COVID test may be indicated
- Blood films ask for 3-5 thick and thin blood film examinations over 48 hours to exclude malaria
- Thick films x3 to identify parasite infection repeated
- Thin Giemsa-stained blood films x 3 show the number of red cells infected and type
- A high parasite count >5 % indicates an increased risk of cerebral malaria. Determine the species of Plasmodium
- Pre-schizont forms indicate an increased risk of cerebral malaria.
- Raised IgM and marked splenomegaly and anaemia with chronic infection
- Rapid Antigen detection tests
Differentials: NB patients can have more than one infection
- Dengue
- Schistosomiasis
- Tick typhus
- Typhoid
- Tuberculosis
- Dysentery
- Influenza
- Viral Pneumonia
- Bacterial Pneumonia
- HIV infection
- Bacterial sepsis - chest and urine
- Bacterial meningitis
- Uncomplicated Falciparum Malaria (Oral treatment)
- Quinine given by mouth for 5-7 days, together with or followed by either doxycycline for 7 days or clindamycin for 7 days
- Malarone (atovaquone with proguanil hydrochloride)
- Riamet (artemether with lumefantrine)
- Complicated Falciparum Malaria
- ABCDE, Support in HDU/ITU
- Watch out for hypoglycaemia and give IV glucose if needed
- Strict fluid balance must be kept and monitor with urine output
- If the patient is seriously ill or unable to take tablets, or if more than 2% of red blood cell are parasitized then either
- IV Artesunate 2.4 mg/kg at 0,12,24 hours may be available for named-patient use. Especially difficult cases (e.g. very high parasite count, deterioration on optimal doses of quinine, infection acquired in quinine-resistant areas of south-east Asia)
- Quinine Sulfate 20 mg/kg IV loading over 4 hours then reduce to 10 mg/kg every 8 hours for 7 days. Given in IV Dextrose. Continue until oral therapy can be started. Can then start Quinine 600 mg TDS to give a full 7-day course. In total, one needs to complete a 7-day course together with or followed by either Doxycycline 200 mg PO for 7 days or Clindamycin.
- Beware hypoglycaemia induced by the infection and quinine
- Treat any suspected bacterial super infection
- Pregnancy
- Falciparum malaria is particularly dangerous in pregnancy
- Most dangerous in the last trimester.
- Can use Oral and intravenous quinine
- Clindamycin should be given after quinine. Do not give Doxycycline if pregnant.
- Specialist advice in difficult cases as Artesunate may be considered
- Advice
- PHE (Public Health England) Malaria Reference Laboratory (020) 7637 0248 (fax) (prophylaxis only) www.malaria-reference.co.uk
- National Travel Health Network and Centre 0845 602 6712
- Monday - Friday (closed Wednesday afternoons and Bank Holidays): 09:00 to 11:45 and 13:00 to 15:45
- Travel Medicine Team, Health Protection Scotland (registered users of Travax only) www.travax.nhs.uk (for registered users of the NHS Travax website only) (0141) 300 1100 (weekdays 2 to 4 p.m. only)
- Birmingham (0121) 424 2358, Liverpool (0151) 705 3100
- London 0845 155 5000 (treatment), Oxford (01865) 225 430