Sepsis, Infection, and Immunologic Disorders
Sepsis
The 2020 Surviving Sepsis pediatric guidance emphasizes recognition, timely antibiotics, and careful fluid titration. For septic shock, give antibiotics within one hour of recognition; for sepsis without shock, within three hours. Obtain cultures before antibiotics when this does not delay treatment. Give 10-20 mL/kg fluid aliquots and start vasoactive support early in fluid-refractory shock. Consider hydrocortisone for catecholamine-resistant shock with suspected adrenal insufficiency.
Immunocompromised hosts
Febrile neutropenia requires empiric broad-spectrum coverage with an antipseudomonal beta-lactam within 60 minutes, with added coverage for suspected line infection or MRSA. Recognize pattern clues: complement deficiency and Neisseria, asplenia and encapsulated organisms, chronic granulomatous disease and catalase-positive organisms, severe combined immunodeficiency and avoid live vaccines, irradiated and CMV-safe blood products.
Traps
Lactate and procalcitonin support but do not define sepsis. Sepsis mimics include DKA, adrenal crisis, anaphylaxis, and cardiomyopathy. Do not wait for a positive culture to treat a shocked child. Avoid fluid loading in a child with known cardiac dysfunction without reassessment. Neonates and immunosuppressed children may lack fever.
Worked rule
A 6-year-old receiving chemotherapy presents with a temperature of 38.4 C, neutrophils 200/microL, and hypotension. Draw cultures, give an antipseudomonal beta-lactam within 60 minutes, begin 10-20 mL/kg aliquots, and start epinephrine if shock persists after 40-60 mL/kg. Reassess after each bolus rather than prescribing a fixed total volume.