A Case of Necrotizing Fasciitis in Which Interleukin‐6 Measurement Helped in the Decision for Large‐Scale Amputation of the Left Shoulder and Arm

ABSTRACT

Background

Necrotizing fasciitis (NF) is a life‐threatening soft tissue infection with rapid progression of necrosis. Early debridement and further surgical procedures are essential, but decision‐making is often difficult. Serum interleukin‐6 (IL‐6) may serve as a valuable diagnostic parameter for monitoring the patient's state and may help in the selection of further therapeutic procedures.

Case Summary

A 52‐year‐old man presented with a fever and severe pain in his left elbow. Laboratory tests showed streptococcal infection, septic shock, and extremely high IL‐6 levels. Intensive care, including wide‐spectrum antibiotics, rapid debridement, large‐scale amputation, and continuous hemodiafiltration using polymethylmethacrylate (PMMA‐CHDF), was performed to ensure the patient's survival. The serum IL‐6 level was constantly monitored to assess the outcomes of therapeutic interventions.

Conclusions

Real‐time serum IL‐6 levels may help assess the immune status of NF patients, guide therapeutic decisions as a part of a comprehensive evaluation, and not hesitate to amputate an extremity to save the patient's life.

Early debridement for necrotizing fasciitis (NF) is essential. Serum interleukin‐6 (IL‐6) measurement may serve as a valuable diagnostic parameter for monitoring patients' septic state and may help to decide on further surgical procedures, including amputation, without delay.

1. Introduction

Necrotizing fasciitis (NF) is a life‐threatening soft tissue infection with rapid progression of necrosis leading to a poor prognosis. Early debridement is therefore essential. Interleukin‐6 (IL‐6) may serve as a valuable diagnostic parameter for monitoring patients' systemic inflammatory response and, as a part of the overall clinical assessment, may help in the selection of further therapeutic procedures, including amputation.

2. Case

A 52‐year‐old man presented to the emergency department (ED) with symptoms of an acute skin infection of the left arm. The patient reported a fever and subsequent severe pain around his left elbow for 3 days after his child was diagnosed with a streptococcal infection. After a visit to a local hospital, he was referred to our hospital with a suspected diagnosis of necrotizing soft tissue infection. On admission, he was hemodynamically unstable, with a GCS score of 15, BP 88/53 mmHg, HR 125/min, SpO₂ 95% on 10 L oxygen, RR 28/min, and temperature 36.7°C. Physical examination showed extensive pain from the left anterior chest to the left fingertips, severe blood blisters and purpura extending from the inner side of the left upper arm to the axilla, and swelling of the left upper arm without subcutaneous emphysema.

Laboratory findings demonstrated leukopenia with WBC 3500/μL and markedly elevated inflammation parameters: CRP 14.36 mg/dL, PCT 96 ng/dL, extremely high IL‐6 21,111 pg/mL, severe lactic acidosis (pH: 7.286, PCO₂ 18.6 Torr, cHCO₃ 8.7 mmol/L, ABE −15.4 mmol/L, anion gap 24.8 mmol/L, lactate 104.1 mg/dL), increased Plt 51,000/μL, and prolonged coagulation times (APTT 46 s, PT 29.3 s, PT‐INR 2.36). In addition, biochemical parameters were elevated: AST 107 U/L, ALT 60 U/L, LDH 334 U/L, γ‐GT 227 U/L, CK 3294 U/L, TBIL 2.97 mg/dL, BUN 52 mg/dL, and Cre 3.4 mg/dL. The APACHE II score was 14, the SOFA score was 5, and the DIC Score [1] was 7, leading to the diagnosis of septic shock with multiorgan dysfunction syndrome (MODS). A rapid test for Group A streptococcus from the wound culture was positive, and blood cultures carried out on admission were positive for Streptococcus pyogenes . Computed tomography showed a diffuse subcutaneous fat tissue infection in the left arm and edema in the ventral portion of the left pectoralis major. Therefore, NF was diagnosed.

Since the patient was hemodynamically unstable, and the rapid streptococcal test was positive for the wound, noradrenaline infusion (0.03 μg/kg/min) was started in the ED along with broad‐spectrum antibiotics (meropenem 1.0 g, daptomycin 500 mg, and clindamycin 600 mg). The patient was immediately intubated in the operating room, and emergency debridement was performed without delay to control the source of infection. Debridement extended from the proximal forearm to the medial part of the arm and into the subpectoral region, involving both the pectoralis major and minor muscles. Then, intensive care was initiated in the ICU, including catecholamine support (noradrenaline 0.23 g/kg/min and vasopressin 2 U/hr), low‐dose steroid therapy (hydrocortisone 200 mg), fluid resuscitation (with a 24‐h fluid balance of approximately +7500 mL), and continuous hemodiafiltration using a polymethylmethacrylate membrane hemofilter (PMMA‐CHDF) [2].

However, instead of improving, an increase of IL‐6 level to 22,700 pg/mL, progressive spread of erythema to the chest, and worsening of the patient's condition were observed. Consequently, large‐scale amputation of the left shoulder and arm was performed the same day, 9 h after admission (Figure 1). Successful amputation caused an immediate decrease in the serum IL‐6 level from 22,720 to 5953 pg/mL 1 h after amputation (Figure 2). Microbiological analysis of the amputated extremity confirmed the presence of S. pyogenes in the left upper arm and axilla, consistent with the previously identified bloodstream infection.

FIGURE 1.

The intraoperative finding during the second operation. In addition to the first operation, that is, debridement extended into the subpectoral region, involving both the pectoralis major and minor muscles, the large‐scale amputation of the left shoulder and arm was performed.

FIGURE 2.

Serial changes of the serum IL‐6 levels during the clinical course. The serum interleukin‐6 (IL‐6) level (blue line) was extremely high upon admission to the ICU. Despite the initial source control of debridement, the general condition did not improve sufficiently, and the serum IL‐6 even increased. After the amputation, the condition improved, and the IL‐6 promptly decreased.

Postoperatively, the IL‐6 level decreased through cytokine modulation by PMMA‐CHDF to 48.6 pg/mL by day 4. Noradrenaline support was gradually reduced from 0.23 to 0.01 μg/kg/min, vasopressin from 2 to 0.5 U/day, and hydrocortisone from 200 to 100 mg/day, indicating improved hemodynamic stability, concomitantly with the decreased IL‐6 level (Figure 2). Antibiotic therapy was adjusted over time, initially including meropenem, daptomycin, and clindamycin, de‐escalated to ampicillin/sulbactam, piperacillin/tazobactam, and cefepime, with micafungin added perioperatively.

On day 3, the patient's hemodynamics stabilized, with optimal BP 107/49 mmHg and HR 84/min. On day 4, his renal dysfunction and inflammation improved, allowing the discontinuation of PMMA‐CHDF. Steroid therapy was discontinued on day 6, catecholamines were stopped on day 7, and extubation was performed on day 13. On day 14, a free flap (superficial circumflex iliac artery perforator flap) procedure was performed to cover the exposed clavicle and subclavian artery. On day 29, split‐thickness skin grafting was performed to aid in wound coverage and reconstruction. On day 32, he was transferred to the general ward of the Plastic Surgery Department in stable condition after the skin graft procedure. On hospital day 62, the patient was discharged ambulatory with a properly healed postoperative wound (Figure 3).

FIGURE 3.

Properly healed postoperative wound. (a) Front side. (b) Lateral side.

3. Discussion

NF is a rare but rapidly progressing and life‐threatening soft tissue infection in which bacteria spread rapidly within the superficial fascia, leading to extensive necrosis, systemic inflammatory response syndrome, and sepsis. If left untreated, especially when the etiology is Streptococcus type A, the condition progresses quickly with a poor prognosis and mortality rates exceeding 30% in patients with septic shock [3]. Early diagnosis is critical for effective management but often remains challenging due to the potential for subcutaneous spread of the infection in clinically unremarkable areas. Although timely debridement is essential for eliminating necrotic tissue, accurately determining the extent of tissue removal poses a clinical challenge [4]. A single debridement session is often insufficient for complete source control, and multiple procedures are needed. Approximately 18.4% of NF cases require limb amputation, often resulting in poor functional outcomes [5]. This case involved intensive care and four surgeries, including wide‐spectrum antibiotics, debridement, amputation, and PMMA‐CHDF to ensure survival. During hospitalization, the serum IL‐6 level was constantly monitored to assess both the patient's immune status and the outcomes after therapeutic interventions.

IL‐6 may serve as a valuable and reliable diagnostic parameter for the diagnosis and monitoring of NF due to its role as a key mediator of inflammation and sepsis [6]. In NF, a rapid and severe inflammatory response to bacterial toxins leads to the massive release of proinflammatory cytokines and hypercytokinemia [7]. A study involving 200 patients analyzed the correlation between cytokine levels (TNF‐α, IL‐1β, IL‐6) and SOFA scores [8]. IL‐6 showed the strongest correlation with the SOFA score [8]. Moreover, the IL‐6 concentration correlated with disease severity [9], progression of septic shock, risk of MODS, and novel sepsis phenotypes.

In the present case, two emergency surgical interventions were performed. The first, debridement, was intended to control the source of infection. However, the IL‐6 levels increased from 21,111 pg/mL before debridement to 22,720 pg/mL afterward, reflecting the increased magnitude of systemic inflammation and worsening of the patient's condition. Despite the patient's young age and an initial attempt at limb preservation, after the comprehensive evaluation considering extensive necrosis and severity of the infection, laboratory and imaging test results, and a persistently rising trend in IL‐6 levels, it was promptly decided to perform a large‐scale amputation of the left shoulder and arm, successfully saving the patient's life. Crucially, amputation resulted in an immediate decrease in IL‐6 levels from 22,720 pg/mL after debridement to 5953 pg/mL at 1 h after amputation and 2283 pg/mL at 3 h after amputation (Figure 2). Furthermore, in postoperative care, PMMA‐CHDF therapy resulted in a significant decrease in IL‐6 levels to 248 pg/mL after 24 h of PMMA‐CHDF, whereas lactate levels decreased after 12 h, reflecting the utility of IL‐6 as both a diagnostic and prognostic biomarker in NF. The overall observed decrease in IL‐6 levels after a remarkable upward trend was likely primarily due to effective amputation and antibiotic therapy, with a possible additional contribution from cytokine adsorption through PMMA‐CHDF.

In most NF cases, aggressive debridement is a sufficient therapeutic approach [10], however, in this case, the patient ultimately lost an arm, sacrificing quality of life, despite survival. Since a definitive decision on further surgical procedures in patients with NF must be made without delay, our findings suggest that real‐time monitoring of serum IL‐6 trends as a part of a comprehensive assessment of NF patients may help in evaluating the immune status of septic patients and guiding timely therapeutic interventions, including amputation when necessary to save the patient's life.

Ethics Statement

Written informed consent was obtained from the patient's next of kin to publish this report in accordance with the journal's patient consent policy.

Conflicts of Interest

The authors declare no conflicts of interest.

Granek Z., Osakabe S., Kajita Y., et al., “A Case of Necrotizing Fasciitis in Which Interleukin‐6 Measurement Helped in the Decision for Large‐Scale Amputation of the Left Shoulder and Arm,” Acute Medicine & Surgery 12, no. 1 (2025): e70090, 10.1002/ams2.70090.

Data Availability Statement

The authors have nothing to report.