Malaria 2.pptx PDF

Malaria Introduction  One of the oldest known diseases  King Tut died of malaria ??  References to malaria have been recorded for nearly 6000 years, starting in China  First advances in malaria were made in 1880 by a French army doctor named Charles Laveran introduction...

Malaria Introduction  One of the oldest known diseases  King Tut died of malaria ??  References to malaria have been recorded for nearly 6000 years, starting in China  First advances in malaria were made in 1880 by a French army doctor named Charles Laveran introduction  A French army doctor in Algeria observed parasites inside red blood cells of malaria patients and proposed for the first time that a protozoan caused disease Charles Louis Alphonse Laveran Introduction  Ronald Ross discovered that mosquitoes transmitted malaria in 1898.  First effective medicine was discovered by Pierre Pelletier and Joseph Caventou. This medicine is called quinine, which comes from the bark of cinchona trees in Peru. Epidemiology Epidemiology  Malaria is the most deadly vector-borne human disease in the world  40% of the world’s population lives in endemic areas  300-500 million clinical cases per year  1.5-2.7 million deaths (90% Africa)  increasing problem (re-emerging disease)  resurgence in some areas  drug resistance (increase mortality)  Males and females are affected equally  Young children aged 6 m to 3 yrs who live in endemic areas are at an increased risk of death due to malaria Etiology  The 5 Plasmodium species known to cause malaria in humans are P falciparum, P vivax, P ovale, P malariae, and P knowlesi  P. vivax is the most widespread malaria infection in the world  P. falciparum and P knowlesi causes the most severe malaria disease in the world and is responsible for the most deaths and morbidity  Transmitted by anopholine mosquitoes Who is at risk?  young children  pregnant women  people with HIV/AIDS  international travelers from non-endemic areas Life Cycle  Characteristics:  Intermediate host : human  Final host : mosquito  Infective stage : sporozoite  Infective way : mosquito bite skin of human  Parasitic position : liver and red blood cells  Transmitted stage : gametocytes  Schizogonic cycle in red cells : 48 hrs/P.v  Sporozoite : tachysporozite and bradysporozite Life Cycle  sporozoites injected during mosquito feeding  invade liver cells  exoerythrocytic schizogony (merozoites)  merozoites invade RBCs  repeated erythrocytic schizogony cycles  gametocytes infective for mosquito  fusion of gametes in gut  sporogony on gut wall in hemocoel  sporozoites invade salivary glands SPECIES CHARACTERISTICS PF PM PO PV 48 72 50 48 Periodicity 50-2000 6-20 9-30 20-50 Parasites/Ml Any Old Young Young RBC Age N N Y Y Hypnozoite 1-2 3->50 1.5-5 1.5-5 Duration (yrs.) MORPHOLOGY  Malarial parasite trophozoites are generally ring shaped, 1- 2 microns in size, although other forms (ameboid and band) may also exist.  The sexual forms of the parasite (gametocytes) are much larger and 7-14 microns in size.  P. falciparum is the largest and is banana shaped, while others are smaller and round. Clinical Features  The incubation period in most cases varies from 7 to 30 days.  The shorter periods are observed most frequently with P. falciparum and the longer ones with P. malariae  Fever in the first week of travel in a malaria-risk area is unlikely to be malaria,  Any individual becomes ill with a fever or flu-like illness while traveling in a malaria-risk area and up to 1 year after returning home, seek immediate medical care for malaria. Clinical presentation of malaria including: Asymptomatic malaria. Mild and uncomplicated. Severe and complicated. Chronic malaria. Asymptomatic malaria.  Asymptomatic malaria infections are still poorly understood.  Asymptomatic malaria remains a challenge for malaria control programs as it significantly influences transmission dynamics.  Asymptomatic malaria that should be the focus of future research towards development of more effective malaria control strategies Malaria causes a flu-like illness and these would include  Fever,  rigors,  headaches,  sweating,  tiredness,  myalgia (limbs and back),  abdominal pain,  diarrhea,  lost of appetite,  orthostatic hypotension,  slight jaundice,  cough,  enlarged liver and spleen  nausea, vomiting. Mild and uncomplicated Uncomplicated malaria is defined as: Symptomatic infection with malaria parasite without signs of severity and/or evidence of vital organ dysfunction.  Malarial Paroxysm 1. Cold stage feeling of intense cold vigorous shivering lasts 15-60 minutes Hot stage 2. Hot stage intense heat dry burning skin throbbing headache e lasts 2-6 hours tag Sw ea 3. Sweating stage s tin ld profuse sweating Co g declining temperature exhausted and weak → sleep lasts 2-4 hours Malaria Paroxysm  P. F may not show classic paroxysms (continuous fever)  paroxysms associated with synchrony of merozoite release  between paroxysms temperature is normal and patient feels well  Severe and complicated malaria It is defined as symptomatic malaria in a patient with P. F infections with one or more of the following complications (assessment of severity) Low blood pressure (Circulatory Lab. abnormality shock) less than 70 mmHg in Bleeding problems, or hemoglobin adults and 50 mmHg in children Septicemia. less than 5 g/dL Hypoglycemia blood glucose less Breathing problems and than 40 mg/dL pulmonary edema (chest x-ray) Acidosis or lactate levels of greater Fluid and electrolyte than 5 mmol/L disturbances Hyperparasitaemia (>10%/ M3 in Acute renal failure (urine 20% / M3 in semi- ml/24 h in adults; 12 ml/kg/24 h in immune) children) Cerebral malaria: Haemoglobinuria. DCL Inability to feed Jaundice. Convulsions ≥ 2 in 24h. Complications of malaria 1- Cerebral malaria  Cerebralmalaria is a rapidly developing encephalopathy as a complications of PF inf.  Malaria occurs in millions of people, but only 20-50 % of the cases develop into cerebral malaria.  Itis unclear why some people develop it and others do not. Rapid diagnosis and treatment is essential Manifestation of CM  Progressive comma & death  A common cause of death for patients with cerebral malaria is acute respitory arrest, which may be a result of the intracranial pressure causing a fatal brain stem herniation.  Most of survival cases have no residual neurologic problems  Only about 10 % of patients surviving cerebral malaria suffer from neurologic deficits such as hemiparesis, hypotonia, or spasticity Complications of malaria 2- hypoglycemia ↑ Insulin released during quinine ttt. ↑ Glucose consumption by massive parasite. ↓ Liver glycogen due to marked anorexia of prolonged time.  Complications of malaria 3- Anemia Child with severe anemia due to malaria  Haemolytic in PF Involve all RBCs even unparasitized cells  Bone marrow suppression.  2ry hypersplenism. No reticulocytosis due to marrow supp. (Dyserythropoiesis)  Complications of malaria 4- black water fever It is a syndrome in malignant malaria due to inadequate quinine therapy. Sudden onset of: Shivering Nausea& vomiting Pallor (anemia) Fever Loin pain Haemoglobinuria (DARK URINE). After few hours : Jaundice, anuria & ARF. Complications of malaria 5- Pulmonary edema Complications of malaria 6- Jaundice  Mild and haemolytic in all pl. types.  Severe in PF due to septic liver affection.  Complications of malaria 7- Algid malaria  A rare complication of tropical malaria (occurring in 0.37% of cases)  Caused by PF involving the gut and other abdominal viscera.  It is characterized by  cold skin, profound weakness, and may be shock. gastric algid malaria: is characterised by persistent vomiting; dysenteric algid malaria: is characterised by bloody diarrhea containing infected RBCs Chronic complications of malaria  Tropical Splenomegaly syndrome (TSS), (hyper-reactive malarial splenomegaly) Tropical splenomegaly syndrome  Occurs due (immunological over-stimulation) to repeated attacks of malarial infection over a long period of time.  Condition is usually seen in malaria-endemic areas  Tropical Splenomegaly Syndrome is characterized by:  Massive splenomegaly & hepatomegaly  marked elevations of serum IgM and anti-malarial antibodies.  Peripheral smear for malarial parasite is usually negative.  Parasites in bone marrow.  Condition may show features of hypersplenism like anemia and thrombocytopenia.  Clinical features of TSS Anorexia, nausea, vomiting, weight loss Symptoms due to anemia or pancytopenia Abdominal pain Abdominal lump Splenic rupture The treatment of tropical splenomegaly syndrome, involve administration of antimalarial drug for a prolonged periods of time. This remove the add-on antigenic stimulus of repeated malarial infections and allow the reticuloendothelial system to return to normal.  The treatment of tropical splenomegaly syndrome.. Cont. Splenectomy plays no role in the treatment of tropical splenomegaly syndrome and should be avoided as it can result in fulminant and overwhelming infections with high mortality. Tropical splenomegaly – DD Portal hypertension – hepatic, extrahepatic Myelo-proliferative diseases Lymphomas Kala-azar CLL Recurrent malaria Symptoms of malaria can recur after a symptom- free periods. Depending upon the cause, recurrence can be classified as either: 1.Recrudescence : It is caused by parasites surviving in the blood as a result of inadequate or ineffective treatment (treatment failure). Relapse commonly occurs