MALARIA Year 4 Paediatrics Notes OmpathStudy

MALARIA Year 4 · Paediatrics Collection: 4TH YEAR ALL NOTES / PAEDS / PAEDRIATICS / AGISA DR -- PROTOZOAL INFECTIONS\n\n MALARIA \n\nLaveran \n\n\n\n\n\nMalaria remains the world's most devastating human parasitic infection. Malaria affects over 40% of the world's population. WHO, estimates that there are 350 - 500 million cases of malaria worldwide.In India 2 million cases and 1000 deaths annually \n\n\n\nThe malaria life cycle is a complex system with both sexual and asexual aspects. cycle of all species that infect humans is basically the same. There is an exogenous sexual phase in the mosquito called sporogony during which the parasite multiplies. There is also an endogenous asexual phase that takes place in the vertebrate or human host that is called schizogeny \n\nA complex Life cycle \n\nHuman Cycle 1 Pre erythrocytic\nschizogony 2 Erythrocytic\nSchizogony 3 Gametogony 4 Exoerythrocytic\nschizogony \n\nEvents in Humans start with Bite of Mosquito  Man – Intermediate\nhost.  Mosquito – Definitive\nhost\n– Sporozoites are\ninfective forms  Present in the salivary\ngland of female\nanopheles mosquito  After bite of infected\nmosquito sporozoites are\nintroduced into blood\ncirculation. \n\n Pre erythrocytic cycle  Sprozoites undergo\ndevelopmental phase in\nthe liver cell  Multiple nuclear divisions\ndevelop to Schozonts  A Schizont contains\n20,000 – 50,000\nmerozoites. \n\nPeriod of Pre erythrocytic cycle\n\n 1 P.vivax 8 days  2 P.falciparum – 6 days  3 P.malariae - 13 – 16 days,  4 P.ovale 9 days\nOn maturation Liver cells ruputure\nLiberate Merozoites into blood stream \n\nErythrocyte cycle  Merozoites released invade red cells  P.vivax infects young erythrocytes  P.malariae Infects old erythrocytes  P.falciparum infects RBC of all ages  The Merozoites are pear shaped 1-5 microns\nin length  The receptors for Merozoites are on red cells\nin the glycoprotein \n\nErythrocytic Schizogony  Liberated Merozoites\npenetrate RBC  Three stages occur \n1 Trophozoites\n2 Schizont\n3 Merozoite \n\nExo-erythrocytic (tissue) phase  P. malariae or P. falciparum sporozoites\ndo not form hypnotizes, develop directly\ninto pre-erythrocytic schizonts in the liver  Schizonts rupture, releasing merozoites \nwhich invade red blood cells (RBC) in liver \n\nGametogony  Merozoites differentiate into Male and female\ngametocytes  They develop in the red cells  Found in the peripheral blood smears  Microgametocyte of all species are similar in\nsize  Macro gametocytes are larger in size. \n\nMosquito cycle Sexual cycle  Sexual cycle will be initiated in the Humans by\nthe formation of Gametocytes  Develop further in the female Anopheles\nMosquito  Fertilization occurs when a Microgametocyte\npenetrate into Macrogametocyte  ZYGOTE is formed matures into OOKINETE  OOKINETE to OOCYST  OOCYST matures with large number of\nSporozoites ( A few hundred to thousands) \n\nMosquito cycle A definitive Host – Mosquito \n\n\n\nMalaria the disease \n 9-14 day\nincubation period \n\nEarly symptoms  The common first symptoms –\nfever, headache, chills and\nvomiting – usually appear 10 to 15\ndays after a person is infected. If\nnot treated promptly with effective\nmedicines, malaria can cause\nsevere illness and is often fatal. \n\nHow Malaria present Clinically  Stage 1(cold stage)  Chills for 15 mt to 1 hour  Caused due to rupture from the host red cells\nescape into Blood  Preset with nausea, vomitting,headache \n Stage 2(hotstage)  Fever may reach upto 400c may last for\nseveral hours starts invading newer red cells. \n\nClinical Malaria  Stage 3(sweating stage)\nPatent starts sweating, concludes the episode\nCycles are frequently Asynchronous\nParoxysms occur every 48 – 72 hours In P.malariae pyrexia may last for 8 hours or\nmore and temperature my exceed 410c \n\nMalaria stages of the disease \n\nMore commonly, the patient presents with a combination of the following symptoms  Fever  Chills  Sweats  Headaches  Nausea and vomiting  Body aches  General malaise. \n\nPeriodicity can be clue in Diagnosis and species relation\n Malaria tertiana:\n48h between fevers\n(P. vivax and ovale) \n Malaria quartana:\n72h between fevers\n(P. malariae) \n Malaria tropica:\nirregular high fever\n(P. falciparum) \n\n SEVERE COMPLICATED MALARIA Confusion, or drowsiness with extreme weakness (prostration). In addition, the following may develop:\n Alteration in the level of consciousness (ranging from drowsiness to deep\ncoma)\n Cerebral malaria (unrousable coma not attributable to any other cause in a\npatient with falciparum malaria)\n Respiratory distress (metabolic acidosis bicarb less than 15 meq/l) \n Multiple generalized convulsions (2 or more episodes within a 24 hour period) \n Shock (circulatory collapse, septicaemia) \n Pulmonary oedema \n Abnormal bleeding (Disseminated Intravascular coagulopathy) \n Jaundice \n Haemoglobinuria (black water fever) \n Acute renal failure - presenting a