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Malaria
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Malaria
* Caused by
parasitic protozoan-Plasmodium
* Disease characterised by fever with rigor, anaemia and splenomegaly
*
200 - 300 million cases globally anually
* 1 - 2 million deaths globally anually
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Malarial
Parasite - Types
* Plasmodium
vivax
* Plasmodium falciparum
* Plasmodium ovale
* Plasmodium malariae
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Clinical
Features of Malaria
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P.
vivax,
P. ovale |
P.
falciparum
|
P.
malariae
|
| Incubation
period |
8-24
days |
8-24
days |
15-30
days |
| Type
of fever |
Tertian
|
Aperiodic
quotidian |
Quartan
|
| Exo-erythrocytic
cycle |
Yes |
No
|
No
|
| Relapse
|
Common
upto 1 year
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Recrudescence
|
Recrudescence
for many years |
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Clinical
Syndromes
Uncomplicated
acute malaria
- Commonest variety, usually due to P. vivax, P. falciparum
- Fever with chills & rigors every 48 hours
- Asymptomatic between paroxysms
Severe
(complicated, pernicious) malaria
- Caused by P. falciparum
- Cerebral malaria is commonest; mortality rate 25-30%
- Other features - severe anaemia, renal failure, pulmonary oedema,
hypoglycaemia, circulatory collapse, acidosis, jaundice, convulsions
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Clinical
Syndromes (Contd…)
Chronic
malaria
- Persistent P. vivax infection may lead to partial immunity
- Asymptomatic low grade parasitaemia
- Splenomegaly may lead to rupture
Tropical
Splenomegaly Syndrome
- Splenomegaly in absence of parasitaemia
- Occurs in endemic areas
- Excessive response to infection with any species of plasmodia
- Splenomegaly regresses with prolonged malarial chemoprophylaxis
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Diagnosis
Demonstration
of parasite in peripheral blood smear
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Treatment
of Malaria
Acute uncomplicated
infection
1) P. vivax,
P. ovale
- Oral chloroquine 10 mg / kg (max. 600 mg) followed by 5 mg / kg
(max. 300 mg) after 6, 24 and 48 hours
- Oral primaquine 15 mg / kg / day x 14 days to prevent relapse
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Treatment
of Malaria (contd.)
Acute
uncomplicated infection (Contd…)
2) P. falciparum
- Chloroquine sensitive - Chloroquine 10 mg / kg (max 600mg) followed
by 5 mg / kg (max300 mg) after 6, 24 and 48 hours
- Chloroquine resistant - Pyrimethamine 25 mg + sulphadoxine 500 mg
tablets - 3 tablets single dose for adults OR - Quinine sulphate 650
mg (10 mg / kg) salt orally T.D.S. X 7 days, plus Tetracycline 250
mg Q.D.S. x 7 days
- Multi drug resistant - Mefloquine 15-25 mg / kg (max 1.5 g) single
dose orally OR - Artesunate 200 mg on first day followed by 100 mg
daily x 4 days
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Treatment
of Malaria (contd.)
Severe falciparum
malaria (including cerebral malaria)
- Quinine I . V . 10 mg / kg over 4 - 8 hours T. D . S x 7 days (oral
therapy when possible)
- Quinine resistant cases - Artesunate 2 mg / kg IM followed by 10
mg / kg after 6 hours on first day, then daily x 4 days OR - Artemether
160 mg (3.2 mg / kg IM) on first day; 80 mg (1.6 mg / kg IM) on days
2 - 5
- Supportive Therapy : I. V. fluids, blood transfusion, etc.
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Chemoprophylaxis
Usually
chloroquine 300 mg base once weekly, starting 1 week before exposure
Alternatives
- Mefloquine, 250 mg base weekly, starting 1 week before exposure
- Doxycycline, 100 mg daily, starting 2 days before exposure
- Chloroquine, 300 mg base weekly, starting 1 week before exposure
+ proguanil 200 mg daily, starting 2 days before exposure
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Anti-Malarial
Drugs
|
Drug
|
Antimalarial
effect
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Adverse
effect
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Comment
|
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Chloroquine
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Blood
trophozoite
of all species
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Bitter
taste nausea, vomiting extrapyramidal reaction psychosis, myopathy
pruritus hypotension (parenteral use) retinopathy (chronic use)
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Should
not be given by IM injection in children
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Quinine
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Blood
trophozoites; gametocytes of P. vivax, P. malariae and P. ovale
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Bitter
taste tinnitus, vertigo high-tone hearing loss, prolonged QT
on ECG Ventricular tachycardia hypoglycaemia haemolysis, thrombocytopenia
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Monitor
QT interval on ECG,safe in pregnancy
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Anti-Malarial
Drugs (contd.)
|
Drug
|
Antimalarial
effect
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Adverse
effect
|
Comment
|
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Mefloquine
|
Blood
trophozoite gametocytes of P. vivax, P. malariae and P. ovale
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nausea,
vomitting, Dysphoria, vertigo, Postural hypotension Convulsions,
encephalopathy
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Acts
more slowly than Chloroquine or quinine
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|
Pyrimethamine
Sulphadoxine
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Blood
stages
|
Megaloblastic
Pancytopenia Steven - Johnsons syndrome
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Contraindicated
in pregnancy
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| Proguanil |
Sporozites
and primary tissue stages |
Megaloblastic
anaemia Renal failure Mouth ulcer Hair loss |
Used
for causal prophylaxis |
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Anti-Malarial
Drugs (contd.)
|
Drug
|
Antimalarial
effect
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Adverse
effect
|
Comment
|
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Primaquine
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Exoerythrocytic
forms of P. vivax, P. ovale gametocytes of P. falciparum
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Abdominal
cramps Haemolysis in G6PD deficiency Methaemo- globinaemia Teratogenic
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Contraindicated
in pregnancy
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Artemesinin
derivatives : Artesunate Artemether Arteether
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Exoerythrocytic
forms of gametocytes of P. falciparum - fastest parasite clearance
time
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Neurological
effects Embryo toxicity
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Contraindicated
in pregnant and lactating women
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