Case presentation
A 71-year-old woman, 154 cm tall, weighing 46 kg, with a history of hypertension and chronic kidney disease, developed lower leg edema one month before hospitalization. She complained of right lower leg pain and a red flare on the day of hospitalization. She visited our emergency room due to the development of dysarthria and gait disturbances. When she arrived at the emergency room, her Glasgow Coma Scale (GCS) score was E4V5M6. However, although she was able to communicate, she had slurred speech and dysarthria. Her pupillary diameter was 3 mm bilaterally, indicating no anisocoria, and the light reflex was normal. Physical examination revealed the following: temperature: 36.9°C, blood pressure: 114/72 mmHg, heart rate: 116 beats/min, respiratory rate: 25 breaths/min, and SpO2: 97% (on room air). Electrocardiogram revealed atrial fibrillation. Multiple areas of erythema were found on both the right and left lumbar and lower abdominal areas, right proximal femoral areas, and left proximal inner femoral area. There were blisters, ruptured blisters, swelling, and aching pain on the right inner femoral area.
Laboratory examination at admission revealed a low white blood cell (WBC) count of 1,000 cells/mm3, elevated C-reactive protein (CRP) of 16.7 mg/dL and elevated procalcitonin level of 30.65 mg/dL, indicating leucopenia with evidence of inflammation and bacterial infection. Her blood urea nitrogen (BUN) level was 68.9 mg/dL and creatinine was 7.29 mg/dL, indicating impaired renal function, and prothrombin time (PT) was 19.3 sec, PT-INR was 1.63, activated partial thromboplastin time (APTT) was 39.2 sec, fibrin degradation products (FDP) were 33.9 μg/mL, and D-dimer level was 10.08 μg/mL, indicating prolonged coagulation and delayed activation of the fibrinolytic system. Blood gas analysis showed increased lactate levels of 4.59 mmol/L.
Brain computed tomography (CT) examination performed to evaluate her neurological status showed an old brain infarction, with no new brain hemorrhage or space occupying lesions. Thoraco-abdominal and pelvic CT examination displayed predominant right lower leg swelling, subcutaneous edema, and increased adipose tissue signals in the entire right femoral region (Figure 1).
Her blood pressure gradually decreased after hospitalization, requiring vasopressors, and hence, continuous administration of noradrenaline at 0.05 µg/kg/min was initiated. The patient then developed disturbance of consciousness (GCS score was E4V3M4). Based on the clinical, laboratory and imaging findings, we diagnosed necrotizing fasciitis from the right lumbar to lower abdominal regions along with septic shock.
Clinical course in the intensive care unit (ICU)
At her admission to the ICU, the patient’s GCS score was E4V2M2, heart rate was 100 beats/min, blood pressure was 80/63 mmHg, and Sequential Organ Failure Assessment score was 11 points. Her systolic blood pressure subsequently decreased to approximately 60 mmHg, GCS score was E3V1M1, and respiration became unstable. Therefore, we performed endotracheal intubation and commenced mechanical ventilation. Since her hemodynamic parameters did not respond to fluid loading and noradrenaline administration, the noradrenaline dose was increased to 0.65 µg/kg/min. Figure 2 shows the time course of changes in hemodynamics on ICU admission day 1. Two hours after ICU admission, we performed right femoral and lower abdominal fasciotomy and purulent drainage. During the procedure, we found right femoral and lower abdominal fascial necrosis. Since the patient also showed deterioration of renal function, we initiated renal replacement therapy. Since endotoxin activity (EA) assay at ICU admission showed increased activity levels to 0.7, we performed CHDF using an AN69ST membrane, and PMX-DHP was added. We subsequently started treatment with two antibiotics: tazobactam/piperacillin and clindamycin (CLDM), and whenStreptococcus dysgalactiaesubsp. equisimilis (SDSE) was detected from culture of blood and genital wound samples, we de-escalated the antibiotics to penicillin-G on ICU day 3. Since the patient had wound infection withPseudomonas aeruginosa , ciprofloxacin was additionally administered. Thrombomodulin-α was administered for treatment of disseminated intravascular coagulation (DIC) from ICU day 1 to day 15. Further, since her urine output was limited to 100 mL/day due to renal failure, high flow CHDF was performed with a dialysate fluid rate of 2000 mL/h for 5 days, which was gradually tapered. Due to the substantial drainage from the wound, crystalloid fluid, fresh frozen plasma and albumin preparations were administered.
Wound lavage was performed daily, along with blunt scraping of subcutaneous and inter-fascial tissue and debridement (Figure 3). Thereafter, the patient’s hemodynamic condition gradually stabilized and noradrenaline was tapered and stopped on ICU day 6. The patient was weaned from mechanical ventilation on ICU day 27. Her subsequent clinical course was favorable and she was transferred from the ICU to the regular ward on ICU day 43.