Clinical judgment by the physician at the time of presentation of these patients is most important

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Diagnosis, Management and Prevention of Dengue Fever
Clinical judgment by the physician at the time
of presentation of these patients is most important

2.5 Billion population is at risk and its annual
incidence is about fifty million patients

KARACHI: Continuing Professional Education department of Aga Khan University recently organized a scientific session where various speakers discussed diagnosis, management and prevention of Dengue Fever which has become a major public health problem in the country during the last few years. Speaking at the occasion Prof. Wasim Jafri Associate Dean of CPE said that we must keep ourselves abreast as to what we need to do and when otherwise we will be faced with many problems. These viruses, he said, are spread by mosquitoes and we need to ensure that there are no breeding grounds for these mosquitoes. In countries like Malaysia and Singapore the authorities have taken appropriate measures and controlled the spread of this epidemic of Dengue Fever. Even a small flower pot which has some water can provide breeding ground for these mosquitoes that is why the authorities in these countries take much stringent measures and those not following the preventive measures are fined.

Dr. Erum Khan was the first speaker who talked about using right tools to detect dengue at the right time. She first gave a historical background and said that Dengue was first reported in 265-420 AD in China. Then it was reported in West Indies and France in 1635, in Panama in 1699, in Japan and Cairo in 1779, Philadelphia in 1780. The world witnessed major dengue epidemic during 1780-1940 owing to shipping industry. Dengue epidemic was also reported in Manila, Bangladesh and Pakistan during 1953-54. She then referred to various studies on Dengue Fever from Pakistan including the one by Dr. Naseem Salahuddin. In 1997 Dengue was reported from Karachi and in 2008, 3840 dengue cases were reported. We had many cases in Punjab and Sindh provinces during 2009-2012. There is a seasonal pattern of dengue fever and it just requires a small amount of fresh water for its breeding.
Speaking about the laboratory diagnosis she said that after infection, patients needs five to seven days to develop fever. PCR can detect dengue in a week’s time but if PCR is not available, IgM is a good test. One should diagnose according to the stages of infection. In case of secondary infection PCR is good but IgM takes long time. She also mentioned about the Elisa antigen capture of Dengue NS-I protein. She also talked about the strength and weakness of various tests including PCR which has sensitivity and specificity of over 90%. We do same day reporting at AKU but she cautioned that do not depend on the laboratory reports alone but take into account the clinical condition of the patient. She also discussed antibody analyses which are mostly used in developing countries. IgG has 94% sensitivity in primary infection. Her conclusions were that PCR is a gold standard for diagnosis of Dengue Fever, early diagnosis helps but beyond five days, IgG also gives good results.
Dr. Mohammad Usman discussed hematological manifestations of Dengue Fever. He pointed out that 2.5 billion population was at risk and its annual incidence was about fifty million. He also talked about pathophysiology, main characteristics, and plasma leakage. The end result of thrombocytopenia is low platelet count and bleeding manifestations. As regards clinical features, he mentioned fever, headache, rash, eye pain, back pain and some of these patients do develop bleeding tendencies. Dengue Fever patients in Grade two and three do require blood and blood products whereas Grade 4 patients must have blood transfusion and get blood products. During 2001-2006 AKU study reported 210 cases with mean age of 29.7 years. Most of these cases were male. During 2006 there was an outbreak of dengue fever. All patients in this AKU study were admitted patients. Fever with bleeding was the main presentation. Out of these 196 were discharged after recovery while seven deaths occurred which was about 3.4% which is much more as international mortality is less than one percent. Clinical judgment of bleeding manifestations by treating physicians is very important, he stated.
Dr. Faisal Mohammad talked about management of Dengue Fever and also referred to the new WHO guidelines. Most dengue fever patients, he said, are usually asymptomatic while few patients have classic dengue. He also talked about dengue hemorrhagic fever and dengue shock syndrome. Discussing natural history of dengue, he said that within seven days patients develop fever, body aches, headache, nausea, vomiting. Most patients are in recovery phase but there is a critical phase between febrile and recovery phase. Plasma leakage is the key. As regards warning signs, he mentioned abdominal pain, tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleed, lethargy, restlessness, enlargement of liver. Recovery phase takes from two to five days when one can witness improvement in appetite. Dengue Fever has been classified as those with and without warning signs, those with plasma leak and severe cases. During history taing, try to ascertain whether the patient can take drink, look for warning signs in the OPD. During diagnosis and assessment group the patients in ABC depending on the warning signs. Group C will have severe manifestations and will require emergency room admission. Group B should also be admitted in the hospital. Group A patients should be given rehydration but make sure it has no colour. Avoid NSAIDs and Steroids. Group A patients should be monitored daily while Group B and C are problematic cases with warning signs. Get baseline Hct and start crystalloids. Continue IV fluids for one to two days. Group C are very sick patients. If patient is in shock, check Hct and give bolus, if BP is better continue rapid infusion. If the patients show improvement, continue fluids. Check Hct and if need be go for Re bolus. All in patients should be put on bolus colloids. Severe dengue fever patients should be in ICU, Group B should be in Wards while Group A patients can be monitored and followed up in OPD.
Dr. Farheen Ali’s presentation was on prevention of dengue fever. She stated that one should take care of underground tanks, flower pots, bath rooms and discarded items like tyers etc., because even a small amount of fresh water can provide breeding ground to these mosquitoes. She also suggested indoor residual sprayings, fogging of open places with water, use of mosquito’s fish, appropriate solid waste management, ensure screening of doors and windows. Do not keep clothes, books untidy or in heaps. One can also use mosquito’s mats, spray coils and after spray keep the rooms closed for twenty five to thirty minutes. Cover all body parts use full pants and long sleeves shirts, use insect repellants, and use insecticidal nets. Vaccines are not yet available but phase-III trials, she said, are underway.
Representatives from civil agencies were also present who also briefly addressed the participants, thanked AKU for their support and guidance besides highlighting the preventive measures government was taking to check the dengue fever. They also pointed out that due to effective measures they had taken their annual expenditures on the use of platelets for these patients has reduced from one crore to just three lac rupees last year. During 2007, they reported over five thousand cases of which twenty seven patients died.
During the discussion it was pointed out that dengue and malaria co-infection was just a co-incidence. The meeting was conducted by Dr. Asim Baig who pointed out that people have to be educated. We have to keep our environment clean and clinical judgment by the physician at the time of presentation of these patients is most important.