Table 10.
Differential Diagnosis From ALF Mimics in Tropics.
| Disease | Clinical and laboratory distinctiveness | Diagnostic test |
|---|---|---|
| Severe falciparum malaria | Paroxysmal fever with chills, enlarged spleen and/or liver, altered sensorium, seizure, coma, severe anemia, hemoglobinuria hypoglycemia, renal failure, DIC, ARDS, shock can be present. Predominant unconjugated bilirubin, mild increase in AST/ALT with a normal INR. |
Microscopy from peripheral blood smear or quantitative buffy coat test or the rapid diagnostic kit (ICT) alone or in combination can detect with a sensitivity and specificity of >95%. |
| Dengue Fever | High grade persistent fever, headache, retro-orbital pain, myalgia, arthralgia, rash (Dengue Fever). Or thrombocytopenia, skin, mucosal bleeds, rise in hematocrit i.e. (Dengue hemorrhagic fever -DHF) or with Hypotension. wide pulse pressure<20 mmHg, or complications like encephalitis, myocarditis, hepatitis, renal failure, ARDS, hemophagocytosis (Dengue shock syndrome) Mild rise in bilurubin, AST/ALT raised 5-20times, AST > ALT Evidence of muscle injury-raised CPK |
NS1 antigen detection IgM, IgG dengue serology |
| Leptospirosis | Fever with chills, headache, myalgia, abdominal pain, conjunctival suffusion, transient skin rash and the severe form, i.e., Weil's disease, with jaundice, proteinuria, hematuria, AKI, pulmonary hemorrhages, ARDS, myocarditis and hepatomegaly. | Raised creatinine phosphokinase levels, serologic test, microscopic agglutination test (MAT), IgM ELISA |
| Scrub typhus | Fever (prolonged, 1–3 weeks), headache and myalgia, breathing difficulty, delirium, cough, jaundice. Hepatomegaly common. Characteristic rash: eschar early in disease Jaundice –hepatocellular, AST/ALT raised <5 times. Normal PT-INR |
Indirect fluorescent antibody: “gold standard” Enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G (IgG) and IgM antibodies: sensitivity and specificity > 90% Weil-Felix: poor sensitivity and specificity |
| Hemophagocytic lymphohistiocytosis (HLH) | Fever, hepatosplenomegaly, lymphadenopathy, neurological manifestations. | Cytopenias, elevated LDH, Serum ferritin, triglycerides and FDPs. Histologically evidenceof hemophagocytosis |
AST, aspartate transaminase; ALT, alanine transaminase; AKI, acute kidney injury; INR, international normalized ratio; DIC, disseminated intravascular coagulation; ARDSDIC, acute respiratory distress syndrome; ICT, immunochromatographic assay.