Morning Report: 9/17/2013

Today’s Morning Report is courtesy of Dr. Grock!

Case:

64 yo male PMH of DM/HTN/prostate ca s/p RT presents with fever.

Important questions?

TRAVEL HISTORY!!!!! Fever pattern, other symptoms…

ROS: neck stiffness and recently returned from West Africa (Liberia).

PE: tachycardia to 100s, febrile orally to 103, +neck stiffness

What next?

IV, labs including malaria smear/blood cx/urine cx, ct head, cxr.

Meds: Tylenol

Meds ordered later: doxycycline, ceftriaxone, vanco (for meningitis + malaria).

ID Rec here: atovaquone 250mg and Proguanil 100mg (malarone) PO.

Malaria Overview

Malaria can’t reproduce in the mosquito in cooler temps (<16degrees for vivax and <21 for falciparum). Duffy, SCD, Hgb C/E, hereditary ovalocytosis, thalassemia, and G6PD provide protection from malaria.

Once parasite burden>2% RBC, mortality steeply increases.

Cerebral malaria – 20% mortality for adults, 15% for children. Obtundation/delirium/abdnormal behavior. Do not always have neuro def or meningeal signs.

– Children commonly have residual neurologic deficit on resolution of coma, but usually goes away by 6 months.

Lab Abnormalities:

Hypoglycemia: common, failure of hepatic gluconeogenesis and increase glucose consumption. Quinine also stimulates pancreatic insulin secretion.

Acidosis: lactic acidosis (failure of hepatic and renal lactate clearance with increased increased anaerobic glycolysis).

Noncardiogenic Pulmonary Edema: unclear pathogenesis. Mortality>80%.

Renal Impairment: ATN, if survive, usually do better. Can do HD/hemofiltration

Anemia: Increased RBC removal by spleen, obligatory RBC destruction, lysis of RBC’s. In Africa, rec blood txif hgb<5 with resp distress, and <3 if not (limited clean blood)

Liver dysfunction: jaundice, acute liver injury

If cerebral malaria, elevated opening pressure on LP.

Treatment: P Vivax in Oceania shows resistance to chloroquine (perhaps increased resistance to falciparum).

-O/w chloroquine, quinine and New drug artemisinin-based are excellent.

– Atovaquone-proguanil excellent, but expensive.

– Artemisinin Combination Treatments: artemisinin derivative for 3 days + other drug. Second line artesunate or quinine + tetracycline, doxycycline, or clindamycin.

-Primaquine is great, but contraindicated if G6PD, neonate, or pregnant

Severe Malaria: quinine 20mg/kg given slow (over 4 hours). Quinidine gluconate: 1-/mg over 1H (frequent ekg x 72 hours). Artesunate (which we don’t have here).

Quinine side effects “cinchism” – tinnitus, decreased hearing, vertigo, hypoglycemia.
Quinidine – same + increased cardiotoxicity.

Mefloquine – N/V/D/abd pain/seizure/psychosis/nightmare

Do NOT WORK
Steroids, heparin, dextran, desferroxamine, TNF alpha inhibitor, high dose phenobarb

Definition of hyperparasitamia – >5% IRBC parasitaemia. Though not correlated to dx severity, may need longer tx.

Seizures-give benzos

Definition of severe malaria: AMS, AKI, acidosis, hypoglycemia, ARDS, hgb<8,DIC, shock, Hemoglobinuria

Other indications for IV theapy: >2% IRBC parasitemia, pregnant, cannot tolerate PO

Exchange transfusion: “controversial and there is no clear evidence base to guide its use”. >10% IRBC parasitemia and other manifestations of severe disease. With the rapid action of artesunate, possibly decrease utility of exchange transfusion. Another paper says >15% rec exchange transfusion, with 5-15% do if “severe symptoms”

Dispo

All pt’s with falciparum should be admitted initially (may rapidly deteriorate), children for at least 24 hours.

For Vivax can have liver hypnozoites survive initial round of meds and => reinfection. Need treatment with primaquine (but worry about G6PD).

Our guy: parasite load <2%. Treated PO x three days, did well, and was discharged. What a happy ending!