Necrotising Soft Tissue Infections: A Single Center's Case Series

ABSTRACT

Necrotising soft tissue infection (NSTI) is a progressive disease with a time‐dependent prognosis; if not promptly treated, it can lead to significant morbidity as well as mortality. Early and aggressive surgical treatment is mandatory for appropriate management. This study reports the diagnostic and therapeutic pathway, surgical treatment and outcomes in a single‐centre series. Data from 40 patients with NSTI treated between 2015 and 2024 were retrospectively analysed for demographic and social information, microbiological results, therapeutic course, clinical outcome and mortality. TC Indication and timing, the role of limb amputation in critical patient survival and reconstruction technique were also reviewed. Fourteen patients (35%) were referred at an advanced stage due to avoidable delay. The mean number of surgical interventions for a single patient was 4. Eight patients (20%) underwent limb amputation. Skin grafts were the most used reconstruction procedure. Seven patients (17.5%) died in the hospitalisation. NSTI is a life‐threatening disease requiring prompt diagnosis and treatment within dedicated clinical pathways. Our series highlights the fundamental role of TC in critical patients or unclear diagnosis, and limb amputation as a life‐saving procedure even at admission in severe cases.

Key Points

• Necrotizing soft tissue infection (NSTI) is a time‐dependent, life‐threatening condition requiring immediate diagnosis and aggressive surgical management.

• Computed tomography (CT) played a pivotal role in critically ill patients and in cases with equivocal clinical presentation.

• Patients required multiple surgical procedures, underscoring the need for repeated and aggressive debridement.

• Limb amputation in advanced stages represents a life‐saving intervention, including cases requiring immediate amputation at admission.

• Delayed referral is frequent, with patients presenting at an advanced stage due to avoidable diagnostic or therapeutic delays.

• Implementation of a dedicated diagnostic and therapeutic pathway is essential to optimize timing of intervention and improve clinical outcomes.

1. Introduction

Necrotising soft tissue infection (NSTI) is a serious and life‐threatening disease. The incidence of NSTI is generally reported as low and ranges from 0.3 to 15 cases per 100 000 population [1, 2, 3].

It is associated with a high mortality rate (23.07%) and it requires long hospital stays, ICU treatment, multiple surgical interventions, resulting in extremely high costs for the healthcare system [4]. Early recognition and treatment are essential, and require centralisation in specialistic centres with a multidisciplinary sepsis pathway. Late diagnosis and referral are still common, which delays the necessary urgent treatment.

NSTI is not a frequent condition in everyday clinical daily routine, but it's not even rare, so that any plastic surgeon will probably face this pathology at least once in his/her professional life. This makes early recognition difficult, and considering its high death rate, it is crucial for both patients and clinicians to be educated on how to promptly recognise early signs [5]. Also, due to its limited incidence, it is difficult to find large studies in the literature, and almost all studies are retrospective.

Current guidelines suggest that these patients must receive early and aggressive surgery; however, many discussed issues remain, such as the need for preoperative imaging and indications for reconstructive surgery or amputation [6].

The aim of this study is to report on the diagnostic and therapeutic pathway, the surgical treatment and outcomes in a relatively large single‐centre series. We present our experience on 40 patients with NSTI treated between 2015 and 2024 and discuss risk factors for morbidity and mortality, effective treatment strategies and outcomes.

2. Materials and Methods

Forty patients diagnosed with NSTI between 2015 and 2024, admitted to a single unit, were identified and their charts were retrospectively reviewed. Informed consent for the use of clinical records for research purposes and for publication of clinical photographs was obtained from all patients. Data were anonymised prior to analysis.

Diagnosis was based on clinical and intraoperative findings (e.g., necrosis of the fascia, loss of fascial integrity, presence of pus with a ‘dish water’ appearance) as well as on microbiology and pathology results.

The following data were collected and analysed: demographic information (gender, age, comorbidities), type of NSTI (I–IV; Table 1), American Society Anaesthesiology score (ASA score), Laboratory Risk Indicator for Necrotising Fasciitis score (LRINEC score), quick Sequential Organ Failure Assessment (qSOFA) and National Early Warning Score (NEWS) at admission, as well as use of preoperative CT scan. ASA is a global preoperative assessment of systemic disease severity and ranges from I (healthy patient) to VI (brain‐dead patient; organ donor). The LRINEC score ranges from 0 to 13 and is a laboratory‐based score developed to support discrimination of NSTI from other soft‐tissue infections, with higher values indicating higher risk. qSOFA ranges from 0 to 3 and is a bedside sepsis‐related score based on altered mentation, systolic blood pressure and respiratory rate; higher values indicate greater risk of adverse outcomes. NEWS is a physiological early‐warning score; higher values indicate increasing clinical deterioration. Samples for microbiological culture examination were obtained during initial surgery for all patients.

TABLE 1.

Necrotising fasciitis classification.

Type of fasciitis	Definition
I	The most frequent (55%–90%) and characterised by a polymicrobial infection. Affected patients are often immunodeficient and show comorbidities, such as diabetes
II	Caused by a monomicrobial infection with Lancefield group A‐Streptococcus but often occurs in association with Staphylococcus aureus . This type in not linked to certain comorbidities, portal of entry are skin lesions or injections
III	Caused by a monomicrobial infection caused by Costridium species, Gram‐negative bacteria or Vibrio spp.
IV	Caused by a fungal infection or zygomycetes

Additionally, we analysed data on isolated microbiological pathogens, anatomical site of infection, triggering causes of fasciitis, risk factors, duration and number of antibiotic therapies, timing of surgical treatment and reconstructive procedures. Outcomes were assessed in terms of survival, limb salvage and hospitalisation length (Figures 1, 2, 3, 4).

FIGURE 1.

(a–f) A case of upper limb necrotising fasciitis (female, 32 years old) reconstructed using skin autografts, DIEP flap and fascia lata graft. (a) Patient‐taken photograph at the onset of erythema and vesicles; initially misdiagnosed as herpes zoster. (b) Clinical appearance upon hospital admission. The patient presents with a large necrotic area on the medial aspect of the arm, along with blisters on the dorsum of the hand, axilla and ipsilateral flank. (c and d) Clinical appearance following the first surgical debridement. (e and f) Intraoperative images of reconstruction using DIEP flap and fascia lata graft for triceps tendon reconstruction. (g) Six months follow‐up.

FIGURE 2.

(a–d) A case of upper limb necrotising fasciitis (male, 22 years old) reconstructed using the dermal substitute matrix (INTEGRA). (a) Clinical appearance upon hospital admission. The patient presents with severe tissue necrosis and signs of systemic infection, requiring immediate surgical intervention. (b) Clinical appearance following completion of surgical debridement. The wound bed is thoroughly cleaned, with active bleeding indicating a healthy tissue base, ready for the next stage of reconstruction. (c) First reconstructive procedure with the application of an acellular dermal substitute. The dermal matrix is placed to provide a scaffold for tissue regeneration and healing. (d) Six‐month postoperative outcome. The upper limb has been successfully reconstructed with the dermal substitute and a partial thickness skin graft, showing good functional and aesthetic recovery.

FIGURE 3.

(a–d) A case of lower limb necrotising fasciitis (male, 48 years old) reconstructed using cadaveric skin allograft. (a) Clinical presentation upon hospital admission. The patient presents with severe necrosis and infection of the lower limb, requiring immediate debridement and intervention. (3) Clinical appearance after the completion of surgical debridement. The wound is clean and prepared for the next step in the reconstruction process. (c) Intraoperative photo showing the insertion of the cadaveric skin allograft. The graft is carefully positioned to cover the exposed tissue and promote healing. (d) Postoperative outcome at 1 month. The lower limb shows signs of successful graft integration, with good wound healing and no signs of rejection.

FIGURE 4.

(a–d) A case of upper limb necrotising fasciitis (male, 48 years old) following vascular surgery. (a) Clinical presentation upon hospital admission. The patient presents with severe necrosis and infection of the upper limb, requiring urgent surgical intervention. (b and c) Intraoperative clinical photos following fasciotomy, abscess drainage and removal of necrotic tissue. The extent of the damage was so severe that the limb was unlikely to have any residual function. (d) Postoperative clinical photos at 6 months.

3. Results

3.1. Patient Data and Microbiology

Data on 40 patients in the study period between 2015 and 2024 were collected. Twenty‐seven patients were male and 13 were female, with a mean age of 60 years (range 21–86 years). Microbiological examination revealed 22 cases of type I and 13 cases of type II necrotising fasciitis; in five cases, it was not possible to detect the pathogens. Culture biopsy antibiograms were performed for all patients. In type I fasciitis, the isolated pathogens were Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa and Enterococcus Faecalis , while the most frequently isolated pathogens in type II fasciitis were Streptococcus pyogenes (Group A streptococcus) and Staphylococcus aureus [7].

Most patients (87.5%) presented with comorbidities, with diabetes mellitus and hypertension (47.5%) being the most common. Four patients (10%) were smokers, and two of them used intravenous substances of abuse (see Table 2).

TABLE 2.

Patient characteristics and clinical parameters.

	Sex	Age	NF type	Anatomical site	ASA score	LRINEC score	qSOFA score	NEWS score	TC	Time from event onset to admission (days)	Surgical procedure (number)	Amputation	Death
1	M	71	I	Lower limb	IV	8	3	13		Not specified	1	x	x
2	M	37	I	Upper limb	III	5	1	4	x	7	8
3	M	55	I	Lower limb	III	8	3	6		0	5
4	M	72	I	Upper limb	IV	5	0	2		15	2	x
5	M	70	I	Lower limb	IV	9	3	12		Not specified	2	x
6	F	77	I	Upper limb	III	3	2	9		Not specified	1	x
7	M	85	I	Genitals	IV	5	2	7		4	4
8	M	64	I	Genitals	IV	6	1	0	x	Not specified	5
9	M	48	II	Upper limb	III	5	3	15	x	0	6	x
10	F	63	II	Upper limb	II	8	1	3	x	4	1
11	M	70	I	Genitals	IV	6	0	3	x	7	4
12	M	58	I	Lower limb	IV	5	3	13		5	4		x
13	M	77	I	Genitals	III	5	2	11		7	3		x
14	M	56	II	Upper limb	IV	8	2	13	x	0	5	x	x
15	M	57	II	Genitals	II	5	2	7		20	6
16	M	86	NA	Genitals	IV	8	1	4	x	Not specified	4		x
17	M	48	II	Lower limb	IV	5	3	14		7	8		x
18	F	47	II	Upper limb	III	5	0	0		5	4
19	M	58	I	Lower limb	III	7	1	8		Not specified	3
20	F	67	I	Lower limb	II	3	1	6		14	2
21	M	23	I	Upper limb	II	5	0	4	x	7	10
22	M	69	I	Lower limb	IV	8	1	4	x	Not specified	3
23	M	63	II	Upper limb	\\	4	3	11		Not specified	1	x
24	F	58	I	Upper limb	\\	5	0	1		22	2
25	F	28	NA	Upper limb	II	5	1	6		4	2
26	M	79	I	Lower limb	III	9	0	3	x	Not specified	2
27	F	78	II	Lower limb	III	7	2	13		Not specified	2
28	M	31	II	Upper limb	II	6	3	14		2	3
29	F	64	NA	Genitals	II	5	0	5		Not specified	2
30	M	65	II	Lower limb	III	6	3	12		2	5
31	F	32	II	Upper limb	I	7	2	9		0	9
32	F	62	NA	Upper limb	II	8	2	11		3	3
33	M	43	I	Upper limb	II	6	3	12		4	10
34	F	54	NA	Upper limb	III	6	2	10		Not specified	2
35	M	78	II	Genitals	III	8	0	4	x	3	2
36	M	77	I	Genitals	III	11	3	14		2	4
37	F	51	I	Genitals	IV	9	1	6	x	1	2		x
38	F	80	II	Upper limb	IV	9	3	9		11	4	x
39	M	66	I	Genitals	III	8	1	2	x	3	2
40	M	21	I	Upper limb	I	1	0	1		2	4

At admission, two patients were ASA I, nine patients were ASA II, 14 patients were ASA III and 13 were ASA IV.

The mean quick SOFA score at admission was 1.6 (range: 0–3), the mean NEWS score at admission was 7.5 (range: 0–15) and the mean LRINEC score at admission was 6.3 (range: 1–11). Detailed data are presented in Table 2.

Preoperative CT was performed in 13 patients (32.5%), usually prior to their referral to our centre. At our unit, under the clinical suspicion of NSTI, early surgical intervention was always prioritised over imaging evaluation; preoperative CT was not routinely required but it was performed in seven cases (20.5%) when patients were hemodynamically stable with low qSOFA, NEWS and LRINEC score, in the presence of diagnostic uncertainty or in case of extensive tissue involvement to optimise surgical plan. In these scenarios, imaging was used to assess the extent of the disease and guide decision‐making, particularly when considering major surgical interventions such as limb amputation. Additionally, preoperative CT scans were performed in patients presenting with necrotising fasciitis of the genital area.

3.2. Locations and Aetiology

In 18 cases, the NSTI involved the upper limb, in 11 cases the lower limb and 11 cases were Fournier's gangrenes. The aetiology was related to previous trauma in 14 cases, to previous surgery in eight cases and to drug administration in four cases (see Table 1). Spontaneous/hydiopatic presentation was recorded in 14 cases.

3.3. Hospitalisation

The time between the onset of symptoms and hospitalisation ranged from 0 to 22 days with a median of 6 days. In all cases, an antibiotic therapy was started prior to the microbiological culture antibiogram. In 40% of cases, the patients were already on targeted antibiotic therapy based on pus samples at admission. Antibiotic treatment lasted an average of 25 days (range of 7–76 days) (see Table 2).

3.4. Surgical Therapy/Outcome/Complications

Surgical treatment was immediate in case of first hospital admission at our centre (45%); in the cases referred from other hospitals, delay in surgery ranged from 1 to 18 days. The average number of surgical procedures per patient was 4 (range: 1–10). Multiple debridements (mean: 3, range: 1–9) were usually performed and vacuum‐assisted closure therapy was a helpful tool in temporarily managing large tissue defects caused by extensive debridement (15%). Three patients healed by secondary intention: two with genital‐perineal necrotising fasciitis and one with upper limb involvement. In 11 cases, fasciotomy incisions were closed primarily (six upper limbs, three lower limbs and two genital regions). A dermal substitute matrix was used in two upper limbs, while skin grafting (either partial‐ or full‐thickness) was performed in eight cases (two upper limbs, four lower limbs and two genital areas). One case involved cadaveric skin allograft for lower limb. Two local flaps were used: a pedicle DIEP flap for genital reconstruction and an advancement flap for hand reconstruction. One upper limb was reconstructed with a free DIEP flap and a fascia lata graft for triceps tendon reconstruction. Eight patients (30.76%) required amputation: four upper limbs (three transhumeral and one glenohumeral disarticulation), two lower limbs at the transfemoral level and two finger amputations. Four patients did not undergo any reconstructive surgery because they died beforehand. The average hospital stay was 26 days. A total of seven deaths were recorded (17.5%) (see Table 2).

4. Discussion

Our study showed that delayed patient referral remains a significant issue, with 35% of delayed referral observed.

Among diagnostic scores, both qSOFA and NEWS scores were reliable predictors of mortality and qSOFA also showed a correlation with amputation risk, while LRINEC did not correlate with either mortality or amputation risk.

Early surgery was effective in reducing life‐risk, with an 82.5% survival rate, and should be prioritised even on radiologic evaluation (CT scans). Amputation is helpful in severe limb fasciitis. Upper limb amputation accounted for 75% of cases, while lower limb amputations represented 25%. Amputation was performed as a lifesaving procedure in two cases, but also in six cases in the subacute phase in case of massive functional damage as a better alternative to difficult and long reconstructive procedures with no functional gain expected. Reconstructive surgery mainly makes use of skin grafts, but local or free flaps can be required for functional reconstruction. NPT, hyperbaric oxygen therapy, dermal substitutes and cadaveric skin grafts are useful tools in the subacute phase for preparing the wounds for definitive reconstruction.

In our series, six over 14 patients (42.8%) who experienced delayed referrals (defined as > 24 h) either required amputation or died. The remaining patients who died or required amputation had high qSOFA and NEWS scores at presentation. Prompt recognition and treatment are crucial to improving prognosis. For instance, one patient who had previously undergone lower limb amputation due to diabetic vascular complications developed necrotising fasciitis at the amputation stump. Initially treated in the orthopaedic department of another facility, the patient was referred to our care only later and ultimately died due to pulmonary complications. Another patient with a history of multiple thrombotic episodes and chronic skin ulcers developed an infection that progressed to necrotising fasciitis; he was initially managed conservatively at home. Three diabetic patients were treated with antibiotics by their general practitioners before being referred to our centre: one had necrotising fasciitis of the lower limb; two had Fournier's gangrene, one referred after 7 days and the other in a state of neglect, making it impossible to determine the duration of symptoms. Finally, a patient with lower limb trauma was initially treated with local wound care and oral antibiotics at a peripheral hospital for 5 days before being transferred to our unit.

Two patients were referred to us 15 and 11 days after initially receiving conservative treatment, including abscess drainage and antibiotic therapy. Both required emergency amputations as life‐saving measures. Similarly, three other patients, unable to report the duration of their symptoms, also underwent amputations.

Clinically, necrotising infections can occasionally be indistinguishable from non‐necrotising infections, especially in the early stages of the disease. Several scores were developed to guide clinicians in diagnosing severe conditions and predicting patient outcomes, such as the LRINEC, qSOFA and NEWS. In this study, we retrospectively evaluated these scores to assess their correlation with mortality and amputation risk. Wong et al. introduced the LRINEC score to categorise patients with clinical suspicion of NSTI. According to Wong, a score greater than 6 suggests NSTI with a probability of 50%–75%, while a score of ≥ 8 is strongly predictive of NSTI, with a probability exceeding 75%. Patients with a score of ≥ 8 are classified as ‘high risk’ [8].

In our study, 14 patients (35%) presented with an LRINEC score of ≥ 8. However, retrospective analysis of their initial blood samples did not reveal a significant correlation between LRINEC values and the risk of amputation or mortality when compared to patients with scores < 8. A Student's t‐test, conducted with a 95% significance level, showed results of t = 0.0337, p = 0.9733 for amputation and t = 0.6316, p = 0.5317 for mortality. These findings suggest that, in our cohort, the LRINEC score alone was not a reliable predictor of these outcomes.

The mean qSOFA score at admission for the entire sample was 1.6 (range: 0–3), while it was significantly higher in patients who underwent amputation, reaching 2.6 in patients. The Student's t‐test confirmed this difference as statistically significant (t = 2.0805, p = 0.0447, p < 0.05). Similarly, when analysing mortality, the qSOFA score was also significantly higher in deceased patients compared to the overall population (t = 2.1659, p = 0.0372).

Conversely, the NEWS score did not show a statistically significant difference between amputated patients and the general population (t = 1.9738, p = 0.0561, p > 0.05). However, when considering mortality, the NEWS score did reveal a significant difference between all patients and those who died (t = 21 826, p = 0.0359, p > 0.05).

These findings suggest that while the LRINEC score may not be effective in predicting amputation or mortality in this cohort, the qSOFA score appears particularly useful in identifying patients requiring amputation. Both qSOFA and NEWS scores, however, are reliable predictors of mortality.

In a literature review, Goh et al. reported a mortality rate of 21.5%, while Hakkarainen et al. reported rates between 20% and 40% [4, 9]. In our series, we recorded seven deaths (17.5%), with four fatalities from limb NSTIs and three from Fournier's gangrene. Cen et al. highlighted that a high LRINEC score, elevated WBC count, low HCT and multiple surgeries were significant predictors of increased mortality. Additionally, higher age, low Hb and multiple wounds were associated with an increased risk of amputation [10]. Nawijn et al. demonstrated that upper extremity NSTIs tend to have a lower mortality rate, but a higher amputation rate compared to NSTIs in other anatomical regions. According to their findings, ASA classification and base deficit at admission are important prognostic factors for upper extremity NSTIs, while NSTIs of the non‐dominant side increase the risk of limb loss [11]. In our series, we observed that the anatomical site of the infection plays a crucial role in determining prognosis. Patients with Fournier's gangrene had a poorer outcome. Moreover, scores like qSOFA and NEWS were significantly correlated with mortality, as was the ASA classification. Among the 13 patients with an ASA classification of IV, six succumbed to their infections, underlining the impact of these factors on patient survival.

To successfully treat NSTI, two important factors are essential: awareness of the disease, despite its rare occurrence and immediate therapy (surgical and antibiotic treatment).

Radiologic imaging (mainly CT scan) can raise or confirm NSTI diagnosis and extent, but inevitably slows down surgery, with potential risks for life and prognosis in aggressive cases, so that literature is not unanimous on its indications.

Wall et al. recommended admitting patients with ‘hard’ signs of NSTI like bullae, necrotic skin or gas on X‐ray, regardless of laboratory findings, to exploration. In cases of no distinct signs, they suggested further testing like CT and laboratory results. The CT adds important value to the clinical and laboratory findings, enhancing the suspicion of NSTI [12]. Korambayil et al. say that CT is a useful adjunct when there is uncertainty of diagnosis but should not be relied on to guide management, especially if there is a delay in obtaining access to it [13]. In the early stages, the radiological findings of the disease are very similar to those identified in uncomplicated cellulitis, including thickening of the dermis and the fascia and increased tissue opacity. The presence of gas dissecting deep fascial planes is a specific sign of NSTI; however, it is only objectified in a limited percentage of patients (approximately 55% of cases) and in advanced stages of the disease. Other frequent characteristics observed are the presence of collections along the fascial plane with possible extension of the oedema to the intermuscular plane. CT is the main imaging modality in the management of this chart, due to its wide availability, low cost, rapidity and high spatial resolution compared to radiography or ultrasound. Although MRI is the most sensitive test for the identification of soft tissue infection, it is not promptly available in an emergency setting [14]. In our study, 11 out of 40 patients underwent preoperative CT. Of these, six patients had a LRINEC score ≤ 8, qSOFA ≤ 1 and NEWS score ≤ 7, while five patients had scores higher than these thresholds. In the first group, CT was requested by us for diagnostic and staging purposes to assess the extent of the infection. In the second group, two CT scans were requested by the hospital where the patients were initially seen, while three were requested by us—one for a patient with Fournier's syndrome and two for patients with upper limb fasciitis. However, other methods for clinical diagnosis, such as the ‘Bedside finger test’, have been described as effective alternatives to imaging techniques. This test, which evaluates the lack of bleeding, tissue resistance and the presence of foul‐smelling, dishwasher‐like pus, is a reliable indicator of NSTI [15, 16]. In our practice, we use the Finger Test during surgery to assess the extent of non‐vital tissue and guide our decision on how much tissue to remove, making it a valuable tool in place of CT for assessing infection spread in real‐time, especially when rapid surgical intervention is required.

In the second group, CT played a critical role in defining the therapeutic approach. Two patients with upper limb fasciitis had a LRINEC score of 5, qSOFA of 3, NEWS score of 15 and ASA III, while a second patient had a LRINEC score of 8, qSOFA of 2, NEWS score of 13 and ASA IV. These patients were clinically unstable, and CT revealed that the infection had spread so extensively in the limb that fasciotomies and abscess drainage were insufficient for adequate source control, justifying amputation.

Therefore, in our experience, CT plays a diagnostic role in patients with low scores, while it is primarily used to guide the therapeutic pathway in those with higher scores.

The key to successful therapy of NSTIs is deliberate, radical and early debridement of all affected tissue, as the infection progresses rapidly with extensive tissue destruction and systemic toxicity. Delay of surgical intervention and inadequate initial debridement cause significantly higher mortality rates [5]. In our case series, among the seven recorded deaths, five patients (71.4%) underwent surgical intervention more than 24 h after symptom onset, due to delays in referral. These patients initially presented at small centres where symptoms were misinterpreted, resulting in a significant delay in referral. The time interval between symptom onset and the first surgical debridement varied significantly, ranging from 0 to 18 days, with an average delay of 2 days. Notably, two patients who experienced the most severe delays underwent their initial surgical procedure at 15‐ and 18‐days post‐symptom onset; both did not survive. These cases highlight the critical impact of early recognition and prompt referral in improving outcomes for patients with NSTIs.

The primary goal in the first surgical debridement should be to resect all infected parts of the fascia completely, including a margin of the healthy fascia. Additionally, all necrotic skin and soft tissue caused by inflammatory thrombosis must be resected; microbiology samples must be taken. Multiple tissue specimens to confirm the diagnosis and adjust the antibiotic treatment are essential.

Antibiotic therapy must be adapted to the microbiology results but started as early as possible. Current recommendations for the initial antibiotic treatment of NSTI include a combination of ampicillin ± sulbactam with clindamycin or metronidazole [5, 17]. In our series, empirical antibiotic therapy was always initiated promptly upon hospital admission, following current literature recommendations. Targeted antibiotic therapy was later adjusted based on microbiological findings and antibiograms. The most employed regimen included ceftazidime/avibactam, linezolid and vancomycin.

The role of amputation in the treatment of NSTI remains controversial, as the scientific evidence in the literature regarding its indications is limited. Goh et al. and Khamnuan et al. reported amputation rates of 15.9% and 8.4%, respectively, but specific indications for amputation in NSTI patients are not thoroughly discussed [4, 18]. Diabetes mellitus as a preexisting condition has been identified as a clinical predictor for limb loss; however, this finding was not consistent with our data [18].

In our series, amputation was necessary in eight patients (20%), a higher percentage likely attributable to a significant rate of late referrals. In two cases, patients were referred 15 and 11 days after their initial hospital visit, resulting in extensive local progression of the infection that made limb salvage unfeasible. In another two cases, amputation was performed as an emergency procedure in septic patients upon hospital admission, proving lifesaving in one patient. Additionally, in two cases, necrotising fasciitis developed on the amputation stump, requiring further amputation to achieve source control. Lastly, two patients underwent finger amputations.

The decision to amputate was guided by specific clinical scenarios, such as life‐threatening sepsis with extensive tissue damage, where the preservation of the limb would require overly radical debridement beyond what the patient could physiologically tolerate. Other indications included circumferentially extensive lesions or cases where the limb was deemed non‐functional due to severe damage.

Moreover, in one patient from our series, delayed amputation to achieve source control resulted in fatal outcomes due to uncontrolled sepsis. This highlights the critical importance of timely radical intervention, including amputation, in advanced cases to prevent systemic spread of infection and improve survival outcomes.

While amputation represents a drastic measure, it is a vital option in cases where the balance between limb salvage and residual function and patient survival tips towards the latter. A thorough evaluation of the extent of tissue damage, functional prognosis of the limb and the patient's systemic condition is crucial in guiding this decision.

Multiple debridements are usually necessary, sometimes within hours after the first operation. The average number of surgical interventions in our patients was four times (range: 1–10) per patient. Goh et al. reported a retrospective study showing that a higher number of debridement surgeries is associated with a reduction in the mortality rate [4]. In our study, patients who died underwent an average of three surgical debridements, while those who survived underwent an average of four interventions. This finding aligns with the literature, where repeated debridements are often necessary to achieve a clean surgical site. Our cases confirm the importance of multiple debridement procedures in ensuring adequate tissue removal and control of the infection, which can significantly influence patient survival outcomes.

Vacuum‐assisted closure therapy (VAC) is a helpful tool in the management and reconstruction of large tissue defects caused by extensive debridement [19]. It stimulates the formation of granulation tissue, promotes wound healing and reduces lesion extension, thus accelerating the process of repair and preparing the wound bed for definitive coverage through various tissue reconstruction methods [14, 20]. However, if applied to wounds with unknown pathogens or potential anaerobic bacteria, the air‐free, closed environment created by the vacuum can exacerbate anaerobic infection [21]. Moreover, VAC therapy is not indicated in the early stages of purulent infections or on necrotic tissue. Once the acute infection is resolved and the patient is stabilised, VAC therapy can be useful for conditioning the wound and extending the intervals between surgical interventions.

In our series, we used VAC therapy in six patients. In these cases, VAC therapy played a crucial role in managing and reconstructing large tissue defects from extensive debridement. It contributed to granulation tissue formation and promoted wound healing, reducing the extent of the lesions and accelerating the wound healing process, which ultimately facilitated the preparation of the wound bed for further reconstructive procedures.

Regarding reconstructive surgery, the choice of the technique depends on multiple factors: the clinical condition of the patient, the size of the wound and the anatomical site of the NSTI. Due to infection, immediate reconstruction is not feasible in most cases. In most cases, autologous meshed skin grafts are the first choice, given the ease of the intervention and the possibility of covering large defects, especially in the limbs, but in some cases, because of the local conditions or the poor general clinical conditions of the patient, temporary solutions were adopted in our series by using dermal substitutes or tissue bank skin to ‘plug the leaks’. This approach is particularly useful when the wound bed is not yet suitable for definitive coverage, either due to ongoing infection, insufficient granulation tissue or significant tissue loss requiring further debridement before stable closure can be achieved. NPT and temporary coverage help protect and prepare the wound, reduce fluid loss and prevent further contamination while preparing the area for definitive reconstruction. It also allows for the stabilisation of other critical factors, such as the patient's coagulation status.

Also, in more delicate areas, such as the genital area, we preferred local flaps to guarantee better coverage and avoid retracting scars. Free flap and more complex functional reconstruction may be needed and are often postponed until patient stability and local control of the infection are reached.

A limitation of this study is its retrospective nature. Also, we included patients who were referred by other hospitals, which results in less detailed information about findings at the initial presentation and treatment and a large range of time to aggressive surgical treatment.

5. Conclusion

Delayed referral remains a common challenge in the management of NSTIs, highlighting the need for improved pathways and networks for timely intervention. While diagnostic scores such as qSOFA and NEWS are valuable, they are more practical in the clinical setting, allowing for faster decision‐making than imaging alone. Early debridement should be prioritised over imaging in cases where rapid intervention is crucial. Imaging techniques, including CT, can be beneficial in selected low‐risk, stable patients or in advanced stages of treatment, when a more detailed understanding of infection spread is required.

Amputation remains a life‐saving procedure in cases of extensive limb involvement or septic patients where tissue damage is beyond salvage. In our study, we recorded six deaths, two from Fournier's Syndrome and four from limb fasciitis. Among these, one patient underwent late amputation, another had significant systemic involvement, and two patients did not undergo amputation. This reinforces the importance of timely surgical decisions and the role of amputation in reducing mortality in certain cases.

VAC therapy proves effective in managing large wounds resulting from fasciotomy procedures, promoting wound bed preparation for definitive coverage. It is especially valuable in preparing the wound for subsequent reconstructive treatments. Reconstructive options depend on various factors, such as wound size, location and the patient's overall health. Skin grafts are the most common method of reconstruction, while dermal substitutes are effective for bridging tissue loss and providing volume. Cadaveric skin allografts are useful for covering large surface areas, and flaps are particularly beneficial in reconstructing skin folds, such as in the genital area.

In summary, early surgical intervention, prompt referral to specialised centres and appropriate use of modern therapies such as VAC and dermal substitutes play a crucial role in managing NSTIs effectively. Additionally, amputation remains an essential tool in reducing mortality in selected cases with severe tissue damage or septic involvement.

Funding

The authors have nothing to report.

Ethics Statement

The authors have nothing to report.

Consent

Written informed consent for the use of clinical records for research purposes and for publication of clinical photographs was obtained from all patients.

Conflicts of Interest

The authors declare no conflicts of interest.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.