A Few Facts About Dengue Fever- Dr M A Aleem Former Vice Principal KAPV Govt Medical College Trichy

A Few Facts About Dengue Fever

Dr M A Aleem
Former Vice Principal
KAPV Govt Medical College
Trichy

Platelet deficiency is not the cause of death in people suffering from Dengue

According to  International guidelines, unless a patient’s platelet count is below 10,000, and there is spontaneous, active bleeding, no platelet transfusion is required. The outbreak of dengue in the City and Hospital beds are full and families are seen running around in search of platelets for transfusion. However what most people do not realize is that the first line of treatment for dengue is not platelet transfusion. It, in fact, does more harm than good if used in a patient whose counts are over 10,000.

The primary cause of death in patients suffering from dengue is capillary leakage, which causes blood deficiency in the intravascular compartment, leading to multi-organ failure. At the first instance of plasma leakage from the intravascular compartment to the extravascular compartment, fluid replacement amounting to 20 ml per kg body weight per hour must be administered. This must be continued till the difference between the upper and lower blood pressure is over 40 mmHg, or the patient passes adequate urine. This is all that is required to treat the patient. Giving unnecessary platelet transfusion can make the patient more unwell.

“While treating dengue patients, physicians should remember the ‘Formula of 20' i.e. rise in pulse by more than 20; fall of BP by more than 20; difference between lower and upper BP of less than 20 and presence of more than 20 hemorrhagic spots on the arm after a tourniquet test suggest a high-risk situation and the person needs immediate medical attention.”

Dengue fever is a painful mosquito-borne disease. It is caused by any one of four types of dengue virus, which is transmitted by the bite of an infected female Aedes aegypti mosquito. Common symptoms of dengue include high fever, runny nose, a mild skin rash, cough, and pain behind the eyes and in the joints. However, some people may develop a red and white patchy skin rash followed by loss of appetite, nausea, vomiting, etc. Patients suffering from dengue should seek medical advice, rest and drink plenty of fluids. Paracetamol can be taken to bring down fever and reduce joint pains. However, aspirin or ibuprofen should not be taken since they can increase the risk of bleeding.

The risk of complications is in less than 1% of dengue cases and, if warning signals are known to the public, all deaths from dengue can be avoided.
DENGUE NS1-Best test is NS1
Cannot be false +ve
Is + from day 1 to 7 ideally.
If on day 1 is -ve, repeat it next day.
Always ask for ELISA based NS1 tests as card tests are misleading.

Value of IgG & IgM dengue-
In a pt with reduced platelets and looking "sick" on day 3 or 4 of illness, a very high titre of IgG with borderline rise in IgM signifies secondary dengue. These pts are more prone to complications.
In primary dengue IgG becomes + at end of 7 days, while IgM is + after day 4.

Immature Platelet fraction/IPF
A very useful test in Dengue for pts with thrombocytopenia.
If IPF in such a pt is > 10%, despite a pl count of 20, 000 he is out of danger & platelets will rise in 24 hrs
If its 6%, repeat the same next day. Now if IPF has increased to 8% his platelets will certainly increase within 48 hrs.
If its less then 5%, then his bone marrow will not respond for 3-4 days & may be a likely candidate for pl transfusion.
Better to do an IPF even with borderline low platelet count.

A low Mean Platelet volume or MPV means platelets are functionally inefficient and such pts need more attention.

What is Dengue?    

Dengue is a fever due to virus spread to humans by Ade's mosquito bite (Day time biter - Morning  to Evening)

What are the symptoms of Dengue fever? 

Dengue presents as High grade fever 103, with Headach, rashes, bleeds, vomiting pain in the eyes, abdomen, joints and muscles as severe bodyache, ..

What are the danger signs requiring admission in hospital?  Patient may require hospitalization in case of Persistent vomiting / severe stomach pain, cold/red  palms&soles, drowsiness / refusal of feeds, bleeds/bruises/Malèna, No Urine output for more than 6hrs
All these Appears only when fever goes away from 5th day to next 48 Hrs,
This s *Critical Phase*of Dengue fever.
Needs close Monitoring when FEVER goes away...

When to do tests?
What tests are to be done?
First 3 days of fever please do CBC, Most important to watch is Platelets count, Packed cell volume(PCV) and NS1Dengue Antigen and Only after 5 days of fever Do Elisa DENGUE Serology test.

What is the treatment for Dengue fever?   

Treatment for Dengue fever is only supportive since antiviral drugs against Dengue virus isn't discovered yet,..
But taking care of Dehydration status & Close monitoring is mandatory,
So Monitor the fluid intake and urine output once in 2to4 hours.

The patient should take adequate fluids, W.H.O approved
liquid.ORS / RELYTE / ELECTRAL /  ORS Ready-mix.

How can Dengue be prevented?
AVOID MOSQUITO BITE as far as possible by applying repellent lotion /cream / spray /  band /sticker,...
Use mosquito net / bat / mosquito repellent gel tray / liquid / matt.
Covering water containers should be encouraged. 
*Keep your Environmental clean*

Nothing to panic since Dengue fever is like any other Viral fever with  mortality of 1%
Very less than
Pneumonia(most dangerous),MEASLES, Diarrhoea, Typhoid, Japanese encephalitis, Hib Brain fever, Hepatitis A,B
(All of those are Vaccine preventable)
So make sure that your kids receive vaccination for all of the above)

*DURING FEVER: Do's*
Close monitoring of hourly temperature, Vital signs BP, Pulse,  liquid intake&urine output are important especially when fever goes beyond 3 to 7days and if fever recurs within 30 days.

As a First aid Please do give tepid- sponging or set AC at 25°¢ in order to cool and bring down the body temperature,
Give Paracetamol as prescribed every 4 to 6th hourly also Nilavembu kudineer, and Plenty of Fluids, Fresh juices, Soups, Normal Food & ORS  till you consult the Doctor

Please give a spoon once in 5 minutes of W.H.O approved ORS  liquid.OR PEDIALYTE OR ELECTRAL OR ORS READY-MIX to prevent most important Dehydration,...

*To prevent Fever*:

AVOID MOSQUITO BITES,
DRINK BOILED& Cooled water adequately
Consume Home made favourite drinks, foods after washing the hands and plates in drinking water.

*DURING FEVER: Don'ts*
Avoid going to quacks,
Avoid injections in muscles during fever,
Avoid over the counter or self medications.
Single injection in the muscle won't cure any fever in fact injection will harm the muscle & nerve...

Avoid water storage without covering, prevent mosquito breeding to prevent Dengue fever,.
*Good Nutritional Status is the Shield to Combat   Complications of  Dengue*
*To Keep your Environment Clean&Friendly
Its each one of our Responsibility*
Thanks,
Take care.