malaria is a parasitic infection common in the tropics

1. MALARIA
OLUM HERBERT
MBChB

2. OUTLINE
• Introduction
• Epidemiology
• Lifecycle
• Pathogenesis
• Clinical presentation
• Complications
• Differential diagnosis
• Investigations
• Management
• Prevention
• Way forward.

3. Introduction
Definition:
• Malaria is an acute febrile illness caused by
infection with plasmodium parasites transmitted
from person to person by an infected female
anopheles mosquito.

4. Epidemiology
• In Uganda, children under 5yrs have 6 episodes
of clinical malaria a year.
• Malaria accounted for about 70% of outpatient
attendances in children under 5yrs.
• Accounted for 50% of admissions in under 5yrs in
Uganda.
Annually
–300 to 500 million cases of malaria &
–700,000 to 2.7 million deaths occur
worldwide, especially in children in tropical
developing countries.

5. PARASITE FORMS.
• Malaria is caused by Plasmodium species, which
are protozoal blood parasites.
• The following 5 species can infect humans:
– P falciparum
– P vivax
– P malariae
– P ovale
– P knowlesi (primate parasite mostly in S.E asia.)

6. LIFE CYCLE AND TRANSMISSION.

7. Malaria life cycle

8. Life cycle
• Bite introduces sporozoites
• Exoerythrocytic stage Sporozoites travel to blood and then liver
• These divide 1000 fold to form schizontes
• One schizonte=thousand merozoites
• Schizonts rupture to release merozoites which invade RBCS of
all ages.
• Merozoites digest Haemoglobin and mature from ring forms to
trophozoites to schizontes over 24hrs in knowlesi,72 in malarae
and 48 in others.
• New merozoites are released by infected RBCs in lysis
• Trophozoites develops into schizonts which raptures to form
merozoites which are released in blood in erythrocytic stage
and they invade RBCs
• Trophozoites form gametocytes or continue to new RBCs.
• The female Anopheles mosquitoes feeds on infected blood
with gametocytes

9. Pathophysiology
 Destruction of parasitized & non-parasitized RBCs, in addition
to bone marrow dyserythropoeisis
 Cytokine production (Tumour Necrosis Factor, Interleukin-1, gamma
interferon)
• Cytoadherence(sticky knobs on infected RBCs)
• Rosetting and Agglutination-infected and uninfected RBCs
stick together & form rosettes viewed under microscope to
clog micro circulation.
• Sequestration of parasitized RBCs-microvascular occlusion to
vital organs.
• Red Cell deformability-less deformable, accelerated sickling
and hemolysis.
• Immune mediated damage of the red blood cells
• Active haemolysis

10. Cont
• Renal failure in the setting of malaria may occur in part
as a result of mechanical obstruction by infected
erythrocytes.
• immune-mediated Glomerular pathology and fluid loss
due to alterations in the renal microcirculation also
probably contribute to renal failure
• Reduced nitric oxide
• Host factors(genetic factors, haemoglobinopathies,
immunity)
• Seizures and coma:
Intracranial sequestration of metabolically active
parasites, cerebral hypoxia, increased intracranial
pressure, cerebral edema, hypoglycaemia,
hyponatremia.

11. Clinical features of malaria
• May be;
• Asymptomatic
• Mild illness (uncomplicated malaria )
• Severe illness (severe or complicated malaria)

12. Uncomplicated malaria
• Intermittent Fever (axillarytemp≥37.5°C)
– Typically acute onset, variable, can be mild,
moderate or high grade
– Shivering/rigors also unusual especially in infants
– May be associated with febrile seizures
– Has3classicalstages,cold,hotandsweatingstages
• Headache
• Diarrhea
• vomiting

13. Cont
• Loss of appetite
• General body weakness
• Rigors and chills
• Joint pains
• Muscle pain
• Mild anaemia
• Mild dehydration
• Enlarged spleen
• In young children - irritability, refusal to eat,
vomiting

14. Complicated malaria
• Malaria is regarded as severe or complicated if
there are asexual forms of P. falciparum in blood
plus one or more of the following complications:
- Severe normocytic anaemia
- Cerebral malaria
- Pulmonary edema/Respiratory distress
- Shock/Circulatory collapse

15. COMPLICATED MALARIA
1.Cerebral malaria
Deep coma (unable to localize a painful stimulus)
Normal CSF
Parasitemia
Management
• Check and treat for hypoglycaemia:
• NGT (for feeding and oral medication)
• Urethral catheter (to monitor urine output)
• Turning of patient frequently to avoid pressure sores

16. 2.Severe anemia
• HB less than 5g/dl or less than 7g/dl in
pregnant mother
• Parasitaemia
Management
• Do blood grouping and crossmatching
• Transfuse patient with packed cells 10-15
ml/kg or whole blood 20 ml/kg especially if
the anaemia is also causing heart failure
• Repeat Hb before discharge and preferably 28
days after discharge

17. 3.Respiratory distress
• Tachypnea
• Nasal flaring
• Intercostal recession in a patient with
• Parasitemia
Management
• Give oxygen

18. 4.Hypoglycemia
• Blood glucose less than 40mg/dl (2.2mmol/l)
• Parasitemia
• Sweating
• Extreme weakness
• Altered conciousness
Management
• Adult: dextrose 25% 2 ml/kg by slow IV bolus over 3-5
min
• Child: dextrose 10% 5 ml/kg by slow IV bolus over 5-7
min
• Monitor blood glucose frequently
• Ensure patient is feeding

19. 5.Circulatory collapse
• Clinical shock;systolic pressure <50mmHg for
children and <80mmhg for adults
• Cold extremities
• Clammy skin
• Parasitemia
Management
• Raise the foot of the bed
• Give sodium chloride 0.9% by fast IV infusion
bolus 20 ml/kg in 15 min
• Review fluid balance and urinary outputs

20. 6.Renal failure
• Urine output less than 12mls/kg/24hrs
• Plasma creatinine >3.0mg/dl
• Parasitemia
Management
• Check to ensure that the cause of oliguria is not
dehydration or shock If due to acute renal failure:
Give a challenge dose of furosemide 40mg IM or
slow IV (child: 1 mg/kg)
• If this fails:
• Refer for peritoneal dialysis or haemodialysis

21. 7.Spontaneous bleeding
• Parasitaemia with
• Unexplained spontaneous bleeding
(haematemesis,malena,or prolonged bleeding
from nose or venipuncture site)
Management
• Transfuse patient with whole fresh blood to
provide lacking clotting factors

22. 8.Repeated convulsions
• Two or more convulsions in 24hrs with
• Parasitaemia
Management
• Give diazepam 0.2 mg/kg slow IV or (in adults) IM
or 0.5 mg/kg rectally
If convulsions still persist:
• Give phenobarbital 200 mg IM/IV
• Child: 10-15 mg/kg loading dose then2.5 mg/kg
once or twice daily if still necessary or
• Or phenytoin 15 mg/kg loading dose

23. 9.Acidosis
• Deep acidotic breathing
• Plasma bicarbonate <15mmol/l with
• Parasitaemia
Management
• Correct fluid & electrolyte balance
• If there is severe acidosis without sodium
depletion:
• – Give sodium bicarbonate 8.4% infusion 50 ml IV
• – Monitor plasma pH

24. 10.Haemoglobinuria
• Parasitaemia
• Haemogloblin in urine (dark coloured urine,no
rbcs)
Management
• Rehydrate the patient
• Assess for anaemia and transfuse if necessary

25. 11.Pulmonary oedema
• Deep breathing
• Fast breathing
• Laboured breathing (nasal flaring,intercostal
recession and chest indrawing)
• Cheyne stokes breathing
Management
• Regulate the IV infusion (do not overload with IV
fluids)
• Give oxygen
• Give furosemide 1-2 mg/kg

26. 12.Impaired consciousness
Parasitemia
Depressed level of consciousness but can
localize a painful stimulus or change of
behavior,confusion drowsiness
13.Jaundice
Parasitemia
Unexplained jaundice

27. 14. Prostration
Unable to sit in a child normally able to do so or
unable to drink in one too young to sit
15.Severe vomiting
Vomiting everything
Not able to breastfeed or drink

28. 16.Severe dehydration
• Sunken eyes
• Coated tongue
• Lethargy
• Inability to drink
Management
• Rehydrate using ORS or IV RL or NS
• Regulate fluids to avoid overlaod and
pulmonary oedema

29. 17.Hyperpyrexia
• Temperature>39.5oC with
• Parasitaemia
Management
• Give paracetamol 1 g every 6 hours
• Child: 10 mg/kg + tepid sponging + fanning

30. 18.Hyperparasitemia
• Parasite count >250,000/microliter
19.Threatening abortion
• Uterine contraction
• Vaginal bleeding

31. Diagnosis
1. Microscopy (Blood smear)
This is the “Gold standard” for diagnosis of malaria
– Thick smear:
Used for screening purposes to detect malaria in low level
parasitaemias
– Thin smear:
Used for species identification and confirm the diagnosis. It
quantifies the parasite load.
Plus System (parasites counted on thick film)
+ = 1-10 parasites per 100 thick film fields (4-40 parasites/mm3)
++ = 11-100 parasites per 100 thick film fields (40-400 parasites/mm3)
+++ = 1-10 parasites per one thick film field (400-4,000 parasites per
mm3)
++++ = >10 parasites per one thick film field (4,000-40,000
parasites/mm3

32. 2. Malaria rapid diagnostic tests (mRDTs)
– Detect specific antigens produced by the malaria
parasites.
– Provide rapid results and can be performed by persons
withlittletechnicalexpertiseandexperience.
– Apositivetestdoesnotalwayssignifymalariaillness.
Other diagnostic tests:
• Indirect fluorescent antibody test (IFA)
Uses fluorescent staining techniques to detect
malaria parasites
• Polymerase chain reaction (PCR)
Use of DNA probes for malaria diagnosis

33. Other lab tests that may be required
• CSF analysis (in cerebral malaria)
• Random blood sugar level
• Hb, Full blood count & differential white cell count
• Renal function tests like Serum creatinine and
electrolytes
• Blood culture (to rule out bacterial infection)
• Chest X-ray
• Liver function tests like AST, ALT, SERUM PROTEINS
• Blood gases, pH (to rule metabolic acidosis)
• Coagulation profiles (in cases of spontaneous
bleeding)
• Blood grouping and cross matching

34. LAB results
• Hypoglycemia
• Hyperlactatemia
• Acidosis
• Increased serum creatinine
• Elevated total bilirubin and abnormal LFTS
• Elevated muscle enzymes(CPK,myoglobin)
• Leukocytosis
• Severe anemia
• Reduced platelets count
• Decreased fibrinogen

35. Differential Diagnosis
• Brucellosis
• UTI
• Meningitis
• Acute cholera
• Trypananomiasis
• Viral hepatitis
• Respiratory tract nfection like pneumonia
• Septicaemia
• Tonsilitis

36. In view of
Intermittent fevers
Muscular, joint and body pains
Sweating; weakness
Headaches
Differ
Orchitis
constipation
Diagnosis-blood cultures
-serum tests detect brucellosis antibodies
Brucellosis

37. In view of
Fever
Diarrhoea
Nausea and vomiting
Differ
Dysuria
Frequency
Diagnosis-urine :urinalysis
microscopy
UTI

38. In view of
Fevers and chills
Coma
Vomiting, fatigue
Loss of weight and appetite.
Differ
Oculomotor palsies
Focal hemisphere signs
Diagnosis
Csf microscopy- AAFBs present
Meningitis esp due to TB

39. In view of
Muscular pains
Vomiting and diarrhoea
Oliguria and dehydration
Loss of consciousness
Differ
Rice water stool
Diagnosis-stool dark field microscopy show the
typical ‘shooting star’ motility of Vibrio
cholerae
Acute cholera

40. View of
Fevers and headache
Drowsiness and tremors
Coma
Differ
Sleepiness
Generalised lymphadenopathy
Trypanosomal chancre
Investigation-thick and thin blood films
-rapid card agglutination tripanosomiasis
test.
Trypanasomiasis

41. In view of
 Jaundice
 Hepatomegally
 Malaise and anorexia
 Joint pains
 Dark urine
Differ
 Pale stool
 Cervical lymphadenopathy
Investigation-serum for viral antigens
liver function tests
Viral hepatitis

42. In view of
Fever
Fatigue
Abdominal pain
Diarrhoea
Decreased level of consciousness
Differ
Productive cough
Shortness of breath
Investigation-CXR
Respiratory tract infections e.g
pneumonia

43. In view of
Fever, shivering
Headaches
Vomiting
Differ
Sore throat
Enlarged inflamed tonsils and cervical lymph
nodes
Investigation-throat swab for culture and sensitivity
Tonsilitis

44. cont
• Septicemia/sepsis
• Other causes of fever…

45. Management
• Definitive treatment: antimalarials
and
• Supportive treatment

46. Uncomplicated malaria
All patients: including children <4 months of age
and pregnant women in 2nd and 3rd Trimesters
First line medicine
• Artemether/Lumefantrine
First line alternative
• Artesunate/Amodiaquine
Second line medicine
• Dihydroartemisin/Piperaquine
• If not available: quinine tablets

47. Cont
Pregnant women 1st Trimester
• Quinine tablets
• ACT may be used if quinine not available

48. Artemether/Lumefantrine
• ACT 20/120mgs
• 4months-3yrs-----1tab
• 3yr-7yrs---------2tabs
• 7yrs-12yrs--------3tabs
• Above 12yrs-------4tabs

49. Complicated or severe malaria
All age groups or patient categories
First line
• IV Artesunate
First line alternative
• IV Quinine
• Or Artemether injection
Pre-referral treatment
• Rectal artesunate

50. General principles
• Manage complications
• Manage fluids very carefully. Adults with severe
malaria are very vulnerable to fluid overload,
while children are more likely to be dehydrated
• Monitor vitals signs carefully including urine
output
• Intravenous artesunate is the medicine of
choice
• If IV route is not possible, use IM route

51. Antimalarial…
Artesunate:
• First line antimalarial for severe malaria
• Treatment for all adults and children, including
infants, pregnant women in all trimesters and
lactating women
• Dose of artesunate;
– 3mg/kg for children <20kg, and 2.4 mg/kg for those
>20kg
– IV or IM at 0, 12 & 24hrs, then daily until the child
can take oral medication but for a minimum of 24 h
even if the child can tolerate oral medication earlier.

52. Antimalarial…
Quinine:
• Dose 10 mg/kg by infusion in 10 ml/kg of IV 5%
dextrose over 4 h. Repeat every 8 h until the
child can take oral medication.
– NB: IV quinine should never be given as a bolus
injection but as a 2–4 h infusion under close nursing
supervision.
– If IV quinine infusion is not possible, quinine can be
given as a diluted IM injection.
– The diluted parenteral solution is better absorbed
and less painful.

53. Antimalarial…
Artemether:
• Dose:
– Give artemether at 3.2 mg/kg IM on admission,
– then 1.6 mg/kg daily until the child can take oral
medication.
• As absorption of artemether may be erratic, it
should be used only if artesunate or quinine is
not available.

54. Supportive management
 Admit to intensive care, if possible
 Place the patient in the lateral or semi-prone position with a
nasogastric tube in place to avoid aspiration
 Monitor respiratory rate, blood pressure, level of
consciousness and other vital signs at least every four hours
 Monitor temperature & reduce high core (rectal)
temperatures, especially >39ºC, by fanning, tepid sponging, &
antipyretics
 Monitor fluid input and urine output with a bladder catheter
in place to avoid fluid overload in the event of renal
impairment or oliguria.

55. • Monitor oxygenation since over aggressive fluid
overload or ARDS can develop.
• Monitor blood glucose for hypoglycemia which can
be present in severe malaria or result from quinine
therapy; treat with glucose as needed
• Check Hct or Hb; transfuse for Hct <20% (Hb <7
g/dL), consider transfusion for those with less severe
anemia if parasitemia is high or if the patient has
respiratory distress or impaired consciousness

56.  Administer vitamin K if abnormal bleeding or disseminated
intravascular coagulation develops and give whole blood,
clotting factors, or platelets as appropriate
 Give diazepam for seizures
 A lumbar puncture should be performed in comatose patients
to exclude bacterial meningitis.
 Other associated or nosocomial infections should also be
looked for and treated.
 Patients who deteriorate suddenly should have cultures taken
and broad-spectrum antibiotics begun that cover gram-
negative bacilli (eg, beta lactam plus gentamicin). Repeat
blood tests every four to six hours to monitor the
parasitologic response

57. Chronic complications of Malaria
• Hyperactive malarial splenomegaly
syndrome(HMSS) or previously known as
tropical splenomegaly
• Quartan malarial nephropathy:Nephrotic
syndrome
• Burkitt lymphoma and EBV Infection:due to
malaria-related immune dysregulation

58. Malaria control
1. Give effective treatment and prophylaxis.
o eliminate parasites from the human population
by early diagnosis and effective treatment
oprotect vulnerable groups with
chemoprophylaxis
ogive IPT to all pregnant women

59. Malaria control
2. Reduce human-mosquito contact
ouse insecticide-treated materials (e.g. bed nets)
odestroy adult mosquitoes by residual spraying of dwellings
with insecticide or use of knockdown sprays
o screen houses
ocarefully select house sites avoiding mosquito infested areas
owear clothes which cover the arms and legs
ouse repellent mosquito coils and creams/sprays on the skin
when sitting outdoors at night z

60. Malaria control
3. Control breeding sites
oeliminate collections of stagnant water where
mosquitoes breed, e.g. in empty cans/ containers,
potholes, old car tyres, plastic bags, footprints, etc. by
disposal, draining or covering with soil, sand
odestroy mosquitoe larvae by dosing stagnant water
bodies with insecticides or with biological methods
(e.g. larvae-eating fish)
4. Give public health education on the above
measures

61. Way forward
• Better protecting vaccine
• The WHO Global Technical Strategy for Malaria 2016-
2030
-Reducing malaria case incidence by at least 90% by
2030.
-Reducing malaria mortality rates by at least 90% by
2030.
-Eliminating malaria in at least 35 countries by 2030.
-Preventing a resurgence of malaria in all countries
that are malaria-free.

62. END
Questions