P1.017: Rethinking Pediatric Sepsis: How the Phoenix Score Transforms Pediatric Care

Introduction: A 7-year-old boy developed refractory hypovolemic and septic shock due to Shigella colitis. This case highlights the rapid progression, diagnostic challenges, and management difficulties of Shigella-induced shock, underscoring the need for early recognition and aggressive treatment to prevent severe complications in pediatric populations.

Case Description: A 7-year-old male presented with a 1-day history of nausea, fever, and severe vomiting/diarrhea.
On presentation, vital signs revealed a temperature (T) of 98.8°F, tachycardia with a heart rate of 177 beats per minute, mild tachypnea with a respiratory rate of 24 breaths per minute, and borderline hypotension with 83/55 mmHg.

Initial laboratory results showed a CBC revealing leukopenia (WBC 4.02 x 10³/μL), CMP: Significant for low bicarbonate (13 mEq/L), elevated BUN (26 mg/dL), creatinine (1.36 mg/dL), glucose (192 mg/dL) and, also elevated anion gap at 21. VBG: pH 7.24, pCO₂ 37, pO₂ 38, HCO₃ 16, Lactate 3.6 mmol/L, Procalcitonin 27.68 ng/mL, CRP 95.8 mg/L and prolonged INR 2.7.

Despite fluid resuscitation, the patient remained hypotensive, requiring norepinephrine and epinephrine. Empiric antibiotics (Piperacillin-Tazobactam and Vancomycin) were initiated.

Imaging studies revealed colitis and a Shigella infection was confirmed by PCR.

The patient was intubated and received prophylaxis for mechanical ventilation, vasopressors, and stress ulcers.

Furosemide was later given for fluid overload.

After stabilization and continued antibiotic treatment, the patient showed steady improvement, was successfully extubated, and weaned off vasopressors.

He made a full recovery and was discharged home in good health.

Discussion: This case highlights a previously healthy 7-year-old who developed refractory mixed shock due to Shigella infection. The patient rapidly deteriorated, requiring intensive care for multi-organ dysfunction, including respiratory failure, cardiovascular instability, synthetic hepatic dysfunction, and hematologic abnormalities, with the Phoenix score of 3 evidenced by:
Spo2: Fio2 ratio was 333.3 (0 points)
Cardiovascular instability necessitating high-dose vasopressor support (Norepinephrine up to 0.5 mcg/kg/min and Epinephrine initiation) (2 points)
Synthetic hepatic dysfunction, demonstrated by an elevated INR of 2.7 (1 point)
Neurological: GCS >10 (0 points).
The Phoenix Sepsis Score (PSS) more comprehensively assessed illness severity compared to SIRS criteria, guiding targeted management. Key interventions included fluid resuscitation, vasopressors, empiric antibiotics, hydrocortisone, and vitamin K for coagulopathy. Nutritional support with TPN was also provided.

This case emphasizes the importance of early recognition of organ dysfunction and individualized, targeted management in pediatric septic shock.

Additionally, it highlights the superior clinical utility of the PSS over traditional inflammatory markers by more accurately capturing the extent and severity of organ system involvement in critically ill children.

Conclusion: Shigella can cause severe septic shock in children. Early hypotension and organ dysfunction warrant aggressive treatment with fluids, vasopressors, and antibiotics.SIRS criteria are still key in identifying patients at risk for sepsis, but the Phoenix score provides more information on illness severity and predicts outcomes.