Infectious Disease

Within 1 hour: obtain blood cultures (before antibiotics), give broad-spectrum IV antibiotics, and begin 30 mL/kg crystalloid bolus for hypotension or lactate >=4. Measure lactate and reassess.

Norepinephrine is the first-line vasopressor. Add vasopressin or epinephrine if MAP remains <65 mmHg despite norepinephrine. Target MAP >=65 mmHg.

Multi-organ dysfunction syndrome (MODS) and disseminated intravascular coagulation (DIC). Also acute kidney injury and ARDS. Source control (drainage/debridement) is essential alongside antibiotics.

A 4th-generation HIV-1/2 antigen/antibody combination immunoassay (detects p24 antigen + antibodies). A reactive result is followed by an HIV-1/2 antibody differentiation confirmatory assay; if discordant, an HIV-1 RNA (viral load) test resolves it.

All patients with HIV, regardless of CD4 count, should start ART as soon as possible. Goal is an undetectable viral load. CD4 count and viral load guide opportunistic-infection prophylaxis and monitoring.

PCP (Pneumocystis jirovecii) prophylaxis with TMP-SMX when CD4 <200. MAC (Mycobacterium avium complex) prophylaxis with azithromycin when CD4 <50. Toxoplasma prophylaxis (TMP-SMX) when CD4 <100.