3. Malaria Continues to flourish in parts of the tropics despite efforts to eradicate it completely Falciparum malaria most severe form of the disease When treated: malaria seldom is fatal Untreated: fatal in 10% of victims, usually as a result of complications
5. Plasmodium vivax, P. malariae, P. falciparum, P. ovale transmitted to humans by mosquito vectors Transmitted by the bite of female Anopheles mosquitoes abound in humid, swampy areas When an infected mosquito bites, it injects Plasmodium sporozoites into the wound The infective sporozoites migrate by blood circulation to parenchymal cells of the liver there they form cystlike structures that contain thousands of merozoites On release, each merozoite invades an erythrocyte and feeds on hemoglobin
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7. The erythrocyte eventually ruptures, releasing heme (malaria pigment), cell debris, and more merozoites that, unless destroyed by phagocytes, enter other erythrocytes The infected person becomes a reservoir of malaria who infects any mosquito that feeds on him This begins a new cycle of transmission P. vivax, P. ovale, P. malariae may persist for years in the liver Chronic carrier state Drug addicts have a higher incidence of the disease Blood transfusions and street-drug paraphernalia also can spread malaria
10. Falciparum malaria can cause Renal failure Liver failure Heart failure Pulmonary edema Disseminated intravascular coagulation (DIC) Circulatory collapse Severe normocyticanemia Seizures Hypoglycemia Splenic rupture Cerebral dysfunction Death
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12. During pregnancy, malaria can lead to: Premature delivery Spontaneous abortion Stillbirth Low-birth-weight infants Malaria-related immunosuppression could possibly lead to an infection with lymphoma viruses Epstein-Barr virus (Burkitt's lymphoma)
14. The patient's history may reveal: travel to an endemic area recent blood transfusion I.V. drug use After an incubation period of 12 to 30 days, the patient may report malaria's prodromal signs and symptoms: Chills Fever Headache Fatigue myalgia interspersed with periods of well-being (the hallmark of the benign form of malaria)
15. Acute attacks (paroxysms) occur when erythrocytes rupture Three stages: cold stage, lasting for 1-2 hrs, ranging from chills to extreme shaking hot stage, lasting for 3-4 hours, characterized by a high fever (up to 107° F [41.6° C]) accompanied by cough, headache, backache, abdominal pain, nausea, vomiting, and delirium wet stage, lasting for 2-4 hours, characterized by profuse sweating
16. Between paroxysms, the patient typically experiences a period of well-being, except in P. falciparum infection Inspection reveals pale skin Rigors can be seen in the cold stage, and flushing, tachypnea, and mental confusion may accompany the hot stage Less frequently, inspection findings may include urticaria, jaundice, and petechial rash Anemia and oliguria may be noted if acute renal failure occurs in the patient with P. falciparum infection
17. If cerebral complications develop, hemiplegia, seizures, altered mental processes, and coma may occur Palpation may reveal moderate splenomegaly and tender hepatomegaly Lymphadenopathy isn't usually present Tachycardia accompanies paroxysms Orthostatic hypotension commonly occurs in the hot stage of paroxysms Chest auscultation may reveal scattered crackles
19. Unequivocal diagnosis depends on laboratory identification of the parasites in red blood cells of peripheral blood smears Romanowsky's staining demonstrates the asexual forms of the parasite Supplementary laboratory test values that support this diagnosis include: decreased hemoglobin (normocytes, normochromicanemia) normal or decreased white blood cell (WBC) count (as low as 3,000/µl) protein and WBCs in urine sediment In falciparum malaria, serum values reflect DIC: a reduced platelet count (20,000 to 50,000/µl), prolonged prothrombin time (18 to 20 seconds), prolonged partial thromboplastin time (60 to 100 seconds), and decreased plasma fibrinogen levels.
22. Malaria is treated with oral chloroquine in all but chloroquine-resistant P. falciparum infection Malaria caused by P. falciparum, which is resistant to chloroquine, requires treatment with oral quinine, given concurrently with pyrimethamine with sulfadoxine and a sulfonamide, such as sulfadiazine Relapses require the same treatment, or quinine alone, followed by tetracycline Mefloquine may also be used for chloroquine-resistant malaria For the hepatic stage of the disease: primaquine phosphate, given daily for 14 days This drug can induce DIC from increased hemolysis of red blood cells (RBCs) contraindicated during an acute attack
23. For travelers spending less than 3 weeks in areas where malaria exists, weekly prophylaxis includes oral chloroquine, beginning 2 weeks before and ending 4 weeks after the trip. Chloroquine and pyrimethamine with sulfadoxine may be ordered for those staying longer than 3 weeks, although combination treatment can cause severe adverse reactions If the traveler isn't sensitive to either component of pyrimethamine with sulfadoxine, he may be given a single dose to take if he has a febrile episode. Any traveler who develops an acute febrile illness should seek prompt medical attention, regardless of prophylaxis measures taken.
25. Chloroquine Perform baseline and periodic ophthalmic examinations Report blurred vision, increased sensitivity to light, and muscle weakness to the physician Consult the physician about altering therapy if muscle weakness occurs. Suggest an audiometric examination before, during, and after therapy. Caution the patient to avoid excessive exposure to the sun to prevent exacerbating drug-induced dermatoses.
26. Primaquine Give drug with meals or antacids Discontinue administration if you observe a sudden fall in hemoglobin concentration or in red blood cell or white blood cell count or a marked darkening of urine, suggesting an impending hemolytic reaction Pyrimethamine Administer drug with meals to minimize GI distress. Check blood counts (including platelets) twice a week. If signs of folic or folinic acid deficiency develop, reduce the dosage or discontinue administration while the patient receives parenteralfolinic acid until blood counts become normal.
27. Quinine Use with caution in the patient with a cardiovascular condition Discontinue administration if you see any signs of idiosyncrasy or toxicity headache, epigastric distress, diarrhea, rash, or pruritus in a mild reaction or delirium, seizures, blindness, cardiovascular collapse, asthma, hemolyticanemia, or granulocytosis in a severe reaction Frequently monitor blood pressure while administering quinine I.V Rapid administration causes marked hypotension.
31. The patient will partake in self-care activities as he can tolerate report decreased levels or absence of pain acknowledge fears, feelings, and concerns about the current situation maintain adequate cardiac output (fluid volume will) remain adequate report an increased energy level remain afebrile (arterial blood gas levels will) return to normal maintain his level of physical mobility (skin will) remain intact experience no further signs or symptoms of infection have no signs or symptoms of complications
33. Assess the patient on admission and daily thereafter for fatigue, fever, orthostatic hypotension, disorientation, myalgia, and arthralgia Enforce bed rest during periods of acute illness Institute standard precautions Protect the patient from secondary bacterial infection by following proper hand-washing and sterile technique Double-bag all contaminated linens and send them to the laundry as an isolation item To reduce fever, administer antipyretics as ordered Document the onset and duration of fever as well as symptoms before, during, and after each episode
34. Administer analgesics as ordered Fluid balance is fragile keep a strict record of intake and output Closely monitor I.V. fluids Avoid fluid overload (especially in falciparum malaria) because it can lead to pulmonary edema and the aggravation of cerebral symptoms Observe blood chemistry levels for hyponatremia and increased blood urea nitrogen, creatinine, and bilirubin levels Monitor urine output hourly Slowly administer packed RBCs or whole blood while checking for crackles, tachycardia, and shortness of breath.
35. If humidified oxygen is ordered because of anemia, note the patient's response, particularly any changes in rate or character of respirations, or improvement in mucous membrane color Watch for and immediately report signs of internal bleeding, such as tachycardia, hypotension, and pallor Encourage frequent coughing and deep breathing, especially if the patient is on bed rest or has pulmonary complications Record the amount and color of sputum Watch for adverse effects of drug therapy and take measures to relieve them
36. If the patient is comatose, change his position frequently and perform passive range-of-motion exercises every 3 to 4 hours If the patient is unconscious or disoriented provide proper supervision use restraints only as needed keep an airway or padded tongue blade available Provide emotional support and reassurance, especially in critical illness Report all cases of malaria to local public health authorities
38. Explain the procedures and treatment to the patient and his family Listen sympathetically and answer questions clearly Suggest that family members be tested for malaria Emphasize the need for follow-up care to check the effectiveness of treatment and to manage residual problems
40. Follow these guidelines for preventing malaria, particularly if you practice or travel in mosquito-infested regions Drain, fill, and eliminate areas of standing water, which are breeding areas of the Anopheles mosquito Install screens or mosquito netting in living and sleeping quarters in endemic areas Use a residual insecticide on clothing and skin to discourage mosquito bites Seek treatment for known cases of malaria
41. Question blood donors for a history of, or possible exposure to, malaria They may give blood if: they haven't taken any antimalarial drugs and are asymptomatic after 6 months outside an endemic area they were asymptomatic after treatment for malaria more than 3 years ago they were asymptomatic after receiving malaria prophylaxis more than 3 years ago Seek prophylactic drug therapy before traveling to an endemic area
44. What is the most deadly form of malaria? What is the vector for malaria? What lab findings would you expect in a patient with malaria? What is the drug of choice for treating P. vivax, P. ovale, and P. malariae ?
45. What is the most deadly form of malaria? Plasmodium falciparum. What is the vector for malaria? The female anopheline mosquito. What lab findings would you expect in a patient with malaria? Normochromicnormocyticanemia, normal or depressed leukocyte count, thrombocytopenia, an elevated sed rate, abnormal kidney and LFTs, hyponatremia, hypoglycemia, and false-positive VDRL. What is the drug of choice for treating P. vivax, P. ovale, and P. malariae ? Chloroquine.