Dengue Fever (DF)

1. Patient A is at D3 of DF; his BP is 90/60. Patient B is at D4 of DF; his BP is 90/75. Which patient do you want to pay more attention to and why?
2. What is the difference between DHF and DSS? And what is compensated and decompensated shock of DHF?
3. Please classify DF.
4. A female patient with day 7 of DF is put on IV drip 4 pints NS. Her HCT is 35%. She is completely well now and she can tolerate oral fluid. How many pints of NS you want to give her? Why?
5. What are the complications of DF that you want to avoid?
6. When do you want to admit patient into ICU?

1. Patient B need more attention, because he is in D4 of DF, which is usually in critical period, with risk of shock, hemorrhage, organ impairment. In fact, patient B also has a narrow pulse pressure (15mmHg), which indicated DSS if there is also signs of plasma leakage and hemorrhage.

2. Difference between DHF and DSS

DHF = DF + Hemorrhage + Plasma Leakage
DSS = DHF + Hypovolemia / Profound Shock / Narrow pulse pressure < 20mmHg

Compensated shock

 - Normal SBP

 - Rising DBP

Decompensated shock

 - Hypotension (SBP < 90 mmHg or MAP < 70 mmHg)

 - Narrow pulse pressure (<20 mmHg)

 - Unrecordable BP

In compensated shock, there is compensation of SBP by tachycardia and peripheral vasoconstriction.

 

3. Classification of DF
Aetiology: Dengue virus type 1, 2, 3, and 4

Infection:

• Primary infection : Classical DF
• Secondary infection : DHF, DSS

Clinical:

• DF without warning signs
• DF with warning signs
• Severe DF

4. Since patient is at the end of critical phase (D7), hemodynamically stable with normalisation of HCT after IV 4 pints of NS, IV fluid should be stop and change to oral fluid to prevent fluid overload. HCT 35% is at lower normal limit for female, but can be due to hemodilution after IV fluid.

5. Complications of DF:

• Shock due to hypovolemia (hemorrhage or plasma leakage)
• Organ impairment
• Fluid overload due to excess IV infusion
• Electrolyte imbalance
• Hyper/hypoglycemia

6. Indication for ICU: 

Severe dengue, which is characterised by at least one of the following:

• Severe plasma leakage leading to dengue shock and/or fluid accumulation with respiratory distress.
• Severe haemorrhages.
• Severe organ impairment (hepatic damage, renal impairment, cardiomyopathy, encephalopathy or encephalitis).

--- UPDATE ---

Additional question:

1. Why patient infected by dengue for the second time has a more severe clinical course like DHF and DSS? 

2. Patient with dengue + elevated liver enzymes = ?

3. What is 7-5-3 regime? When is it indicated in patient with dengue?

4. A 5 years old child with DF, in recovery phase, still has subfebrile temperature, but he is not able to swallow paracetamol tablet, what should you do to reduce the fever?

1. Second Dengue fever is more severe and dangerous and it might end up with DHF/DSS. As we know, Dengue virus has 4 serotypes. Second Dengue infection is made up of more than 1 serotype. Second infection tends to be presented with phenomenon of antibody-dependent enhancement (ADE). In ADE, DENV (Dengue virus) will enhance leucocytes to produce non-neutrolizing antibody. These antibodies will bind with DENV and supposedly they are to neutralize the DENV. However, after binding with the DENV, they are not only transfered into wrong compartment of dendritic cells and not being neutralized, they also replicate within the host cells. Thence, after replication, host cell lysis occurs and it is followed by release of virus into the blood stream (viraemia).

2. Dengue+ raised liver enzyme = liver involvement (replication of virus inside the liver cell+ cell lysis and it leads to release of new viruses and liver enzyme)= dengue hepatitis

3. 7-5-3 regime is refered 7cc/kg/h for 1h, 5cc/kg/h for 2h, 3cc/kg/h for 4h. This regime is used in compensated shock of Dengue grade III.

4. We seldom give T. PCM to children but we do give Syr. PCM. If they refuse/unable to tolerate oral PCM, then rectal PCM would be recommended.

There are few cases in which the patients should not die: severe Dengue, bronchial asthma, DKA, malaria. It is because these conditions can be reverted and the patient should live after adequate resuscitation and appropiate management.