Clinical Algorithm of Bojang et al for Predicting Malaria in a Gambian Child with Fever or History of Fever (Modified Olaleye Score)

 

Patient selection: child with fever or history of fever within the previous 48 hours

 

Exclusions: chronic disease, severe malnutrition, HIV-positive, organ insufficiency, abscess or other obvious cause for fever

 

Criteria for the clinical diagnosis of malaria:

(1) parasitemia >= 5,000 per µL (1 parasite per high power field, but magnification not given)

(2) axillary temperature >= 37.5°C

 

Parameters:

(1) sleepy

(2) feeding

(3) cough

(4) shivering

(5) feeling hot

(6) cough not heard

(7) pallor of palm

(8) absence of rash

(9) respiratory rate

Parameter	Finding	Points
feeling sleepy	absent	0
	present	1
feeding	normal	0
	reduced	1
cough	absent	1
	present	0
shivering	absent	0
	present	1
feeling hot	absent	0
	present	3
silent cough	absent	0
	present	1
pallor of palm	absent	0
	present	1
rash	absent	1
	present	0
respiratory rate	normal or decreased	0
	increased	1

 

where:

• The main differences from that of Olaleye et al is that (a) feeling hot is assigned 3 rather than 1 point, (b) parasite density was not known in advance and (c) age range not specified, only a history of fever.

 

malaria score =

= SUM(points for all 9 terms)

 

Interpretation:

• minimum malaria score: 0

• maximum malaria score: 11

• A positive score could be either >= 7 or >= 8.

 

Performance if done by fieldworkers:

• For a score >= 7 the sensitivity was 88% and specificity 62%; the positive predictive value was 55%

• For a score >= 8 the sensitivity was 70% and specificity 77%; the positive predictive value was 62%.

• Most malaria transmission occurred in the rainy season. The predictive value during the rainy season was higher than during the dry season.