Changing scenario of malaria: a study at Calcutta.

Sixty cases of P. falciparum and 165 cases of P. vivax were studied clinically along with species identification of parasite after examination of the blood slide by experts at Calcutta. It was observed that malaria had been changing its clinical profile. The classic paroxysm is evident only in 40% cases of P. falciparum and 47.27% of P. vivax malaria, but the difference between the two groups is not statistically significant. On the other hand continuous or remittent type of fever has been observed in 40% and 27.27% cases of P. falciparum and P. vivax respectively, while absence of classic paroxysms of fever, in association with splenomegaly when present, poses a diagnostic difficulty with enteric fever. Association of jaundice in 40% and 9.09% cases with P. falciparum and P. vivax respectively along with hepatomegaly in 80% and 63.63% in them in conjunction with nausea and/or vomiting leads to clinical mimicry with infective hepatitis. Splenomegaly which has been described as cardinal feature of malaria was observed in 40% cases with P. falciparum and only in 18.18% cases of P. vivax malaria and this is a clear deviation from earlier description and this difference between the two groups is highly significant at 99% level of confidence. Co-existent enteric fever was observed in 3.33% of falciparum and 2.6% of vivax malaria, though this difference is not statistically significant. Acute respiratory distress was observed in 6.6% of P. falciparum malaria only. Oliguria with impaired renal function was noted in 5% cases of P. falciparum malaria. The present study has also noted convulsion or coma in 8.33%, purpura with disseminated intravascular coagulation in 3.33% and black water fever in 3.33% cases in falciparum malaria which were not observed in cases with vivax malaria and these differences are statistically significant. However, stupor with bilateral extensor planter response was observed in two cases (1.3%) of vivax malaria.