Dengue Fever and Platelet Count

[admin]

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.**

Article Reproduced from IMA CGP WhatsApp Journal - Posted by Dr Dhanavel

[uamohammed]

This article is very nicely presented and whoever is the author deserves compliments. 'The formula 20' is a good guideline to keep in mind while treating Dengue fever. Thank you again

UA Mohammed

[admin]

Dr Thippeswamy from J S S medical college,Mysore, writes:

Dear Sir/Madam, Of late we are seeing lot many cases similar to Dengue like illness. However they are serologically negative for Dengue, leptospirosis, Weil Felix, malaria, enteric fever. Please guide us how to further evaluate these cases for any specific viruses. Your valuable inputs will be highly appreciated.

Thank you.

[admin]

Dr Sridhar has forwarded this reply:

There r several viral fevers which have no specific diagnosis unless u do virus isolation or direct or indirect antibodies measurements or specific demonstrable anti body antigen reactions. Like Clinical Enteric Fevers there where there is a definite features of Enteric Fever like coated tongue headache coming with fever Brady cardiac diarrhea and abdominal discomfort serology may be negative culture may not yield.

Clinically Empirically u treat as Enteric.Empirically means based on common prevalence of diseases. Malaria is common in Rameshwaram Clinical Diagnosis of Malaria in the absence of investigation is justifiable. On ur case serology for Dengue is negative but there r some features suggestive of Dengue like low platlet count Ascities Effusion around Gall bladder Pleural Effusion fall of BP and raise in Haemocrit more than 45 raise of haemocrit as we follow up Hgic spots all indicate a situation like Dengue.Usual spot tests may be negative.

But go in for next higher Elisa tests.Do Viral culture or study the common Viral fevers prevalent in ur area.is Kyassnur Forest disease.Supportive measures as IVF RLNS to maintain BP have flat bed Playlet infusion if there is Hgic manifestation. Pls counsel the pt about limitations. We cure at times,relieve at times ,Comfort always is a golden saying. Dr.A.Selvaraj jeyaseelan MD.

[admin]

Dr Sridhar has forwarded this article from The Times of India:

LUCKNOW: Over 600 patients of viral fever are being treated by doctors at government hospitals daily. However, less than 20% fall in the categories of dengue, malaria or chikunguniya.

But platelet and white blood cell (WBC) count of about 15-20% patients is going down. Former head of civil hospital and expert in medicine, Dr H N Tripathi terms the condition as `fever and myalagia syndrome' (FMS). Myalagia, it may be noted, is a condition marked by acute muscle pain and cramps in the body. The remaining symptoms are of simple seasonal viral flu.

"The syndrome is marked by leucopenia (drop in the number of white blood cells), thromocytopenia (drop in the platelet count), altered liver function, retro-orbital pain (pain behind the eyes), chills and anorexia (nausea and loss of appetite). In some patients, the involvement of central nervous system is also seen. Death due to a similar condition has not been reported till now," added Dr Tripathi, who now works with a private hospital.

[admin]

Dr.Thirupathy consultant physician Apollo hospital Karaikudi, writes:

Our experience in rural apollo reach hospital was around 4000 dengue inpatients with more of DHF/DSS. Nearly 15% pts were elisa negative.these are the pts who detoriate the most in icu.but still have similar features of dengue with acalculus cholecystitis,capillary leaks.they don't have other immunocompromised features also. We generally manage with aggressive iv fluids, ffp,. We prefer very high antibiotics suspecting sec bacterial sepsis. Generally pt came up very well. Our overall mortality in dhf with or without elisa positive was less than2%. Always sss, leptospirosis,chikungunia, typhus were our DD list.