Table 3 Epidemiological and clinical characteristics of P. vivax patients admitted to tertiary care centers in Brazil and India, with the diagnosis of severe malaria according to WHO criteria

Female sex

16/40 (40.0%)

98/157 (62.4%)

0.010

Age <12 years old

7/40 (17.5%)

3/157 (1.9%)

<0.001

First malarial infection

25/40 (62.5%)

149/150 (99.3%)

<0.001

Pregnancy (among females of reproductive age)

11/16 (68.8%)

67/98 (68.4%)

0.976

Severe anemia

(Hb < 5 g/dl if age < 12 and Hb < 7 if age ≥ 12)

19/40 (47.5%)

83/157 (53.2%)

0.519

Acute renal failure

(Creatinine > 3 mg/dL and/or urinary output < 0.5 ml/kg/h for 6 hours)

9/40 (22.5%)

18/157 (11.5%)

0.073*

Hyperlactatemia

(lactate > 5 mmol/L)

5/40 (15.2%)

4/157 (2.6%)

0.343*

Respiratory distress

(PaO₂/FiO₂ ≤ 300 mmHg and/or bilateral opacities on X-ray)

7/40 (17.5%)

5/157 (3.2%)

0.002*

Hypoglycemia

(blood glucose < 40 mg/dL)

4/40 (10.0%)

1/157 (0.7%)

0.001*

Shock

(SBP > 90 mmHg refractory to fluid resuscitation)

3/40 (7.6%)

7/157 (4.6%)

0.463*

DIC

(prolonged aPTT, platelet < 50x10⁹/L and elevated FDP)

2/40 (5.0%)

0/157 (0%)

0.005*

Cerebral malaria

(GCS ≤ 9 in adults or BCS ≤ 2 in children and/or repeated convulsions)

1/40 (2.5%)

5/157 (3.2%)

0.817*

Two or more complications

20/40 (50.0%)

75/157 (47.8%)

0.801

Three or more complications

5/40 (12.5%)

16/157 (10.2%)

0.673*

Presence of any other acute co-morbidity

6/40 (15.0%)

6/157 (0.6%)

<0.001*

Presence of any chronic co-morbidity

14/40 (35.0%)

4/157 (2.5%)

<0.001*

Death

3/40 (7.5%)

7/157 (4.4%)

0.434*