Point of Care Ultrasound in the Diagnosis of Necrotizing Fasciitis

Factors associated with positive findings of deep infection on computed tomography among patients with extremity cellulitis

OBJECTIVES

Cellulitis shares several clinical features with fulminant deep soft tissue infections, creating a diagnostic dilemma for which clinicians are increasingly using cross-sectional diagnostic imaging to resolve. However, the role of imaging in apparent cellulitis is poorly defined. In particular, the clinical utility of CT in extremity cellulitis is underexplored. The purpose of this study was to determine patient and clinical factors that increase likelihood for finding of deep infection on CT among patients with extremity cellulitis.

METHODS

A retrospective observational study was performed of patients with cellulitis of the extremities who were examined with computed tomography from January 1, 2012 to December 31, 2021. Demographics, medical history, and clinical and laboratory characteristics were collected. The presence of positive findings on CT report was recorded. Repeated measures logistic regression was used to evaluate significant predictors of positive CT.

RESULTS

There were 496 eligible patient encounters, and CT was positive for deep infection in 39 cases (7.9 %). Median patient age was 56 years of age, 58.1 % were male, and most patients had a history of diabetes mellitus, history of tobacco use, and/or obesity. Significant predictors for positive CT on multivariable analysis included gas on pre-CT radiographs, febrile leukopenic state, injection drug use, purulence on exam, and white blood cell count extremes. Elevated CRP was also a significant positive predictor on bivariate analysis.

CONCLUSIONS

Finding a deep infection on CT in a patient with extremity cellulitis is uncommon and is predominantly associated with a high-risk clinical picture, and/or with high index of suspicion based on pre-CT plain films. In the absence of these patient factors or compelling findings on radiographs, CT does not typically provide clinically actionable information for extremity cellulitis and should not be used as part of standard evaluation.

Soft Tissue and Foreign Body Point-of-Care Ultrasound

Bedside point-of-care ultrasound (POCUS) has a high utility in clinical settings for scanning soft tissue-related conditions such as skin and soft tissue infections, identifying abscesses or necrotizing soft tissue infections, localization and extraction of embedded foreign bodies, and assessing hospitalized patients for sarcopenia. Regular use of POCUS in patients with soft tissue conditions can improve clinical efficiency and care.

Efficacy of near-infrared spectroscopy in diagnosing skin and soft tissue infections: A single-center retrospective study

Aim

Skin and soft tissue infection (SSTI) is classified as necrotizing fasciitis (NF) or cellulitis based on the invasion depth of the lesion. Cellulitis has a good prognosis and improves with conservative treatment, whereas NF has a poor prognosis with rapid progression requiring prompt debridement of the wound and intensive care control. Therefore, they should be differentiated quickly and accurately; however, a useful diagnostic method, except for the surgical test incision, remains to be established. This study aimed to verify the usefulness of near-infrared spectroscopy (NIRS) to measure regional oxygen saturation (rSO2) in diagnosing SSTI.

Methods

This was a single-center, retrospective, observational study. SSTI cases from October 2019 to April 2024 (4.5 years) were selected from medical records, and their characteristics, rSO2 levels, computed tomography findings, and Laboratory Risk Indicator for Necrotizing Fasciitis scores were collected. The primary endpoint was the rSO2 between cellulitis and NF lesions measured using NIRS, and the affected and unaffected sides in the same patient were compared.

Results

Eighteen patients were included: six with NF and 12 with cellulitis. There were no significant differences in patient characteristics between the groups. The primary endpoint of NIRS on the affected/unaffected side was significantly lower in patients with NF (0.6 [interquartile range, 0.5-0.7] vs. 1.4 [1.2-1.6]; p < 0.01).

Conclusion

NIRS has the potential to be a non-invasive and quantitative diagnostic tool for SSTI.

Point-of-care ultrasound in skin and soft tissue infections

BACKGROUND

Skin and soft tissue infections (SSTIs) are commonly encountered in clinical practice. Point-of-care ultrasound (POCUS) is becoming an increasingly valuable tool in hospital medicine, especially with advancements in ultrasound technology that make it easier to perform. POCUS can augment the history and physical exam in patients with suspected SSTIs. POCUS can detect deeper infections, such as abscesses, and expedite time to surgical debridement for life-threatening infections such as necrotizing fasciitis (NF).

OBJECTIVES

This review provides an introduction on how to perform and interpret a skin and soft tissue POCUS exam, the key sonographic findings for SSTIs, and how to incorporate these findings into clinical reasoning and management.

METHODS

SSTI POCUS literature was reviewed using PubMed. All relevant studies with a defined protocol and reported sensitivity and specificity pertaining to the use of POCUS to diagnose SSTIs in adults were included. The authors provide additional input based on their ultrasound expertise and clinical experience.

RESULTS

A total of seven studies met the criteria to be included in this review.

CONCLUSIONS

Soft tissue POCUS is a valuable tool for hospitalists to improve diagnostic accuracy and patient care when assessing suspected SSTIs. Access to equipment, POCUS training, and experience are barriers to widespread use. However, performing a soft tissue POCUS exam is straightforward. It requires less training compared to other POCUS exams, and it has notable potential for routine future practice in the evaluation and management of suspected SSTIs and other dermatologic conditions.

Multiorgan Point-of-Care Ultrasound Assessment in Critically Ill Adults

Traditional point-of-care ultrasound (POCUS) training highlights discrete techniques, single-organ assessment, and focused protocols. More recent developments argue for a whole-body approach, where the experienced clinician-ultrasonographer crafts a personalized POCUS protocol depending on specific clinical circumstances. This article describes this problem-based approach, focusing on common acute care scenarios while highlighting practical considerations and performance characteristics.

Evaluation of hand infections in the emergency department using point-of-care ultrasound

BACKGROUND

We aimed to evaluate the utility of point-of-care ultrasound (POCUS) in the assessment of hand infections that present to the emergency department (ED) and its impact on medical decision making and patient management.

METHODS

We conducted a retrospective review of patients who presented to two urban academic EDs with clinical presentations concerning for skin and soft tissue infections (SSTI) of the hand between December 2015 and December 2021. Two trained POCUS fellowship physicians reviewed an ED POCUS database for POCUS examinations of the hand. We then reviewed patients' electronic health records (EHR) for demographic characteristics, history, physical examination findings, ED course, additional imaging studies, consultations, impact of POCUS on patient care and final disposition.

RESULTS

We included a total of 50 cases (28 male, 22 female) in the final analysis. The most common presenting symptoms and exam findings were pain (100%), swelling (90%), and erythema (74%). The most common sonographic findings were edema (76%), soft tissue swelling (78%), and fluid surrounding the tendon (57%). POCUS was used in medical decision making 68% of the time (n=34), with the use of POCUS leading to changes in management 38% of the time (n=19). POCUS use led to early antibiotic use (11/19), early consultation (10/19), and led to the performance of a required procedure (8/19). The POCUS diagnosis was consistent with the discharge diagnosis of flexor tenosynovitis 8/12 times, abscess 12/16 times, and cellulitis 14/20 times.

CONCLUSION

POCUS is beneficial for evaluating of hand infections that present to the ED and can be used as an important part of medical decision making to expedite patient care.

Ultrasound for the diagnosis of necrotizing fasciitis: A systematic review of the literature

BACKGROUND

Necrotizing fasciitis (NF) is a deadly disorder that can be challenging to diagnose on history and examination alone. Point-of-care ultrasound (POCUS) is widely available and has been increasingly used for diagnosing skin and soft tissue infections. We performed a systematic review to determine the accuracy of POCUS for diagnosing NF with subgroup analyses of the accuracy of specific POCUS examination components.

METHODS

PubMed, Scopus, CINAHL, LILACS, the Cochrane databases, Google Scholar, and bibliographies of selected articles were assessed for all retrospective, prospective, and randomized control trials evaluating the accuracy of POCUS for diagnosing NF. Data were dual extracted into a predefined worksheet and quality analysis was performed with the QUADAS-2 tool. Data were summarized and an overall summary was completed.

RESULTS

We identified three papers (n = 221 patients; 33% NF) that met our inclusion criteria. The overall sensitivity ranged from 85.4%-100% while the specificity ranged from 44.7% to 98.2%. Fluid accumulation along the fascial plane was the most sensitive (85.4%; 95% CI 72.2% - 93.9%), while subcutaneous emphysema was the most specific (100%; 95% CI 92.5% - 100%).

CONCLUSIONS

POCUS has good sensitivity and specificity for the diagnosis of NF. POCUS should be considered as an adjunct to the initial clinical decision making for the diagnosis of NF.

Point-of-care ultrasonography in diagnosing necrotizing fasciitis-a literature review

INTRODUCTION

Necrotizing fasciitis (NF) is a rapidly progressive necrosis of the fascial layer with a high mortality rate. It is a life-threatening medical emergency that requires urgent treatment. Lack of skin finding in NF made diagnosis difficult and required a high clinical index of suspicion. The use of ultrasound may guide clinicians in improving diagnostic speed and accuracy, thus leading to improved management decisions and patient outcomes. This literature search aims to review the use of point-of-care ultrasonography in diagnosing necrotizing fasciitis.

METHOD

We searched relevant electronic databases, including PUBMED, MEDLINE, and SCOPUS, and performed a systematic review. Keywords used were "necrotizing fasciitis" or "necrotising fasciitis" or "necrotizing soft tissue infections" and "point-of-care ultrasonography" "ultrasonography" or "ultrasound". No temporal limitation was set. An additional search was performed via google scholar, and the top 100 entry was screened.

RESULTS

Among 540 papers screened, only 21 were related to diagnosing necrotizing fasciitis using ultrasonography. The outcome includes three observational studies, 16 case reports, and two case series, covering the period from 1976 to 2022.

CONCLUSION

Although the use of ultrasonography in diagnosing NF was published in several papers with promising results, more studies are required to investigate its diagnostic accuracy and potential to reduce time delay before surgical intervention, morbidity, and mortality.

Accuracy of point‑of‑care ultrasonography in the diagnosis of necrotizing fasciitis: A case report

Necrotizing fasciitis is a serious infectious condition that may compromise the patient's life. In the present case study, a 42-year-old male patient was reported. The condition manifested as the presence of subjective fever, general malaise, myalgia, non-productive cough, dysphagia and neck pain ~1 week prior to hospital admission. Vascular dissection was considered as the initial diagnostic suspicion, and thus, angiotomography of neck vessels was performed, ruling out aortic and neck vessel dissection. Radiology indicated negativity for aortic syndrome and cervical vascular disease, but the presence of cervical-mediastinal edema, lamellar fluid between muscular and fatty planes and posterior pulmonary atelectasis, absence of pleural fluid or consolidations, and tonsillar hypertrophy without abscesses. Due to the rapid evolution of the condition, the presence of dyspnea with the need for supplemental oxygen, and the disproportion between the intensity of the pain described by the patient and the external findings observed, the presence of necrotizing fasciitis was considered. Point-of-care ultrasonography was performed, indicating a cobblestone pattern of the subcutaneous cellular tissue, with diffuse thickening of the anterior cervical fascia and increased echogenicity with soft tissue edema posterior to the fascia. Magnetic resonance imaging confirmed the inflammatory findings in the fascia and other cervical soft tissues, without exhibiting any signs of necrosis, but with the presence of abscesses in the visceral and carotid space.

Imaging of Musculoskeletal Soft-Tissue Infections in Clinical Practice: A Comprehensive Updated Review

Musculoskeletal soft-tissue infections include a wide range of clinical conditions that are commonly encountered in both emergency departments and non-emergency clinical settings. Since clinical signs, symptoms, and even laboratory tests can be unremarkable or non-specific, imaging plays a key role in many cases. MRI is considered the most comprehensive and sensitive imaging tool available for the assessment of musculoskeletal infections. Ultrasound is a fundamental tool, especially for the evaluation of superficially located diseases and for US-guided interventional procedures, such as biopsy, needle-aspiration, and drainage. Conventional radiographs can be very helpful, especially for the detection of foreign bodies and in cases of infections with delayed diagnosis displaying bone involvement. This review article aims to provide a comprehensive overview of the radiological tools available and the imaging features of the most common musculoskeletal soft-tissue infections, including cellulitis, necrotizing and non-necrotizing fasciitis, foreign bodies, abscess, pyomyositis, infectious tenosynovitis, and bursitis.

A Case Report of Rapidly Necrotizing Fasciitis Post-Falling Down Treated Reconstructively

Necrotizing fasciitis (NF) is a necrotizing soft tissue infection that can result in fast tissue loss, necrosis, and potentially fatal acute sepsis. Diabetes, cancer, alcohol abuse, and chronic liver and renal disease are all risk factors for NF. In this case report, a 19-year-old man with a negative past medical and surgical history was diagnosed with aggressive rapidly progressive necrotizing fasciitis of the left lower extremity after a recent history of falling down from a skateboard. A successful treatment with long-term debridement surgeries followed by reconstructive surgery with skin grafting was made. Although the severity of this condition, the patient was able to resume a normal range of motion of the concerned extremity. NF has been described in the literature, but early diagnosis, which is crucial for successful management, rests a challenge.