Diagnostic accuracy of contrast-enhanced CT for neck abscesses: A systematic review and meta-analysis of positive predictive value.

OBJECTIVES: To review the diagnostic accuracy of contrast-enhanced computed tomography (CT) in differentiating abscesses from cellulitis in patients with neck infections, using surgical findings as the reference standard. MATERIALS AND METHODS: Previous studies in the last 32 years were searched from PubMed and Embase. Because of partial verification bias (only positive abscess findings are usually verified surgically), sensitivity and specificity estimates are unreliable, and we focused on positive predictive value (PPV). For all studies, PPV was calculated as the proportion of true positives out of all positives on imaging. To estimate pooled PPV, we used both the median with an interquartile range and a model-based estimate. For narrative purposes, we reviewed the utility of common morphological CT criteria for abscesses, such as central hypodensity, the size of the collection, bulging, rim enhancement, and presence of air, as well as sensitivity and specificity values reported by the original reports. RESULTS: 23 studies were found reporting 1453 patients, 14 studies in children (771 patients), two in adults (137 patients), and seven including all ages (545 patients). PPV ranged from 0.67 to 0.97 in individual studies, had a median of 0.84 (0.79-0.87), and a model-based pooled estimate of 0.83 (95% confidence interval 0.80-0.85). Most morphological CT criteria had considerable overlap between abscesses and cellulitis. CONCLUSIONS: The pooled estimate of PPV is 0.83 for diagnosing neck abscesses with CT. False positives may be due to limited soft tissue contrast resolution. Overall, none of the morphological criteria seem to be highly accurate for differentiation between abscess and cellulitis.

Unusual Phlegmon in the Plantar Foot of a Healthy Patient.

Phlegmons are unencapsulated collections of inflammation that track along soft tissues in various parts of the human body. These soft-tissue lesions are uncommon in the lower extremities and can be difficult to identify and treat. This article presents a case of a plantar foot phlegmon in a nondiabetic patient that was recalcitrant to debridement and antibiotics. The patient's aseptic phlegmon completely resolved with surgical debridement and iodoform packing. This case report demonstrates the role of advanced imaging in the diagnosis of lower-extremity phlegmons and the importance of thorough surgical debridement and packing for successful resolution.

[Sonographic diagnosis of tonsillar abscesses: Our experience and a systematic review]. / Sonografische Diagnostik tonsillärer Abszesse: Eigene Erfahrungen und eine systematische Übersicht.

BACKGROUND: Transcutaneous sonography has been an integral part of imaging diagnostics in the head and neck region for several decades. Especially in the imaging of abscesses of the tonsillar fossa, sonography is a fast, safe, and cost-effective diagnostic method. This paper aims to provide an overview of the currently published studies in terms of diagnostic value. MATERIAL AND METHODS: systematic literature search in the following online databases: PubMed und MEDLINE according to the search terms: transcutaneous ultrasound, tonsillar abscess, peritonsillar abscess, intratonsillar abscess, peritonsillar cellulitis, parapharyngeal abscess. Evaluation of the scientific relevance of the papers according to established criteria. RESULTS: The publications were analyzed in terms of clinical application, clinical diagnosis, and diagnostic accuracy. Sensitivity and specificity are reported between 67 % - 100 %, and 50 % - 93 %, respectively, depending on the study and patient cohort. CONCLUSIONS: In the synopsis of the currently published results, transcutaneous sonography promises a high potential to improve the diagnosis of peritonsillar abscess and allows a reliable differentiation to peritonsillar cellulitis. This fact seems crucial for the clinical management of patients with suspected abscesses.

Lymphangitis Carcinomatosa in Neck Soft Tissue: Computed Tomography Findings With Emphasis on Differentiation From Cellulitis.

OBJECTIVE: Lymphangitis carcinomatosa (LC) is a rare form of metastasis. The purposes of this study were to evaluate computed tomography (CT) findings associated with LC in neck soft tissue and to determine those that were useful in distinguishing LC from cellulitis. METHODS: Contrast-enhanced CT images of 26 patients with pathologically confirmed LC (n = 5) and clinically proven cellulitis (n = 21) were reviewed retrospectively. The following CT findings were evaluated and compared between the 2 groups: subcutaneous fat infiltration, enlargement of muscle, thick irregular enhancement of the superficial cervical fascia, grouping of micronodules, focal intramuscular enhancement, localized fluid collection, and nodular skin thickening. RESULTS: Thick irregular enhancement of the superficial cervical fascia (80.0% vs 0%, P < 0.0005), grouping of micronodules (60.0% vs 0%, P < 0.005), and focal intramuscular enhancement (60.0% vs 4.8%, P < 0.05) were significantly more frequent in LC than in cellulitis. Other findings did not show statistical significance between both groups. CONCLUSIONS: When soft tissue swelling is present in the neck with either thick irregular enhancement of the superficial cervical fascia, grouping of micronodules, or focal intramuscular enhancement, the possibility of LC should be considered especially in patients with underlying malignancy.

Point-of-Care Ultrasound on Management of Cellulitis Versus Local Angioedema in the Pediatric Emergency Department.

OBJECTIVES: To evaluate whether ultrasound can differentiate between cellulitis and angioedema from insect bites in pediatric patients. METHODS: A prospective, pre-post study in an urban pediatric emergency department of patients younger than 21 years with soft tissue swelling from insect bites without abscesses were enrolled. Treating physician's pretest opinions regarding the diagnosis and need for antibiotics were determined. Ultrasound of the affected areas was performed, and effects on management were recorded. Further imaging, medications, and disposition were at the discretion of the enrolling physician. Phone call follow-ups were made within a week of presentation. RESULTS: Among 103 patients enrolled with soft tissue swelling secondary to insect bites, ultrasound changed the management in 27 (26%) patients (95% confidence interval [CI], 18-35%). Of the patients who were indeterminate or believed to require antibiotics, ultrasound changed management in 6 (23%) of 26 patients (95% CI, 6%-40%). In those patients who were believed not to require antibiotics, ultrasound changed management in 12 (16%) 77 patients (95% CI, 7%-24%). Patients with diagnosis of local angioedema achieved symptom resolution 1.4 days sooner than patients diagnosed with cellulitis (mean, -1.389; 95% CI, -2.087 to -0.690; P < 0.001). No patient who was initially diagnosed as local angioedema received antibiotics upon patient follow-up. CONCLUSIONS: Point-of-care ultrasound changed physician management in 1 of 4 patients in the pediatric emergency department with soft tissue swelling secondary to insect bites. Ultrasound may guide the management in these patients and lead to improved antibiotic stewardship in conjunction with history and physical examination.

Diagnosis and treatment of the invasive extension of bacteria (cellulitis) from chronic wounds utilising point-of-care fluorescence imaging.

Early diagnosis of wound-related cellulitis is challenging as many classical signs and symptoms of infection (erythema, pain, tenderness, or fever) may be absent. In addition, other conditions (ie, chronic stasis dermatitis) may present with similar clinical findings. Point-of-care fluorescence imaging detects elevated bacterial burden in and around wounds with high sensitivity. This prospective observational study examined the impact of incorporating fluorescence imaging into standard care for diagnosis and management of wound-related cellulitis. Two hundred thirty-six patients visiting an outpatient wound care centre between January 2020 and April 2021 were included in this study. Patients underwent routine fluorescence scans for bacteria (range: 1-48 scans/patient). Wound-related cellulitis was diagnosed in 6.4% (15/236) of patients. In these patients, fluorescence scans showed an irregular pattern of red (bacterial) fluorescence extending beyond the wound bed and periwound that could not be removed through cleansing or debridement, indicating the invasive extension of bacteria (wound-related cellulitis). Point-of-care identification facilitated rapid initiation of treatments (source control and antibiotics, when warranted) that resolved the fluorescence. No patients had worsening of cellulitis requiring intravenous antibiotics and/or hospitalisation. These findings demonstrate the utility of point-of-care fluorescence imaging for efficient detection and proactive, targeted management of wound-related cellulitis.

Preseptal Versus Orbital Cellulitis in Children: An Observational Study.

BACKGROUND: Preseptal and orbital cellulitis are two types of infection surrounding the orbital septum with very different potential outcomes. Our aim was to describe key differential features of both conditions, laying special emphasis on diagnostic and therapeutic tools. METHODS: A retrospective review of patients admitted to a tertiary hospital over a 15-year period (January 2004-October 2019) was conducted. We included 198 patients with preseptal and 45 with orbital cellulitis. Descriptive statistics were performed to examine the available information. RESULTS: Statistically significant differences were found between patients with preseptal and orbital cellulitis regarding age (3.9 ± 2.14 vs. 7.5 ± 4.24 years), presence of fever (51.5% vs. 82.2%), and preexisting sinusitis (2% vs. 77.8%) (all P < 0.001). Diplopia, ophthalmoplegia and proptosis were only present in orbital cellulitis (P < 0.001). Median values of C-reactive protein were significantly higher among children with orbital involvement [136.35 mg/L (IQR 74.08-168.98) vs. 17.85 (IQR 6.33-50.10), P < 0.0001]. A CRP>120 mg/L cut-off point for orbital cellulitis was obtained. Early CT scans were performed in 75.6% of suspected orbital cellulitis and helped detecting complications at an early stage. Abscesses were revealed in 70.6% of cases, especially medial subperiosteal abscesses (58.8%). All patients received intravenous antibiotics, whereas corticosteroids were preferred in patients with orbital implication (8.6% vs. 73.3%, P < 0.001). Only 26.7% of patients required additional surgery. CONCLUSIONS: Clinical presentation and CRP are extremely sensitive for differential diagnosis of preseptal and orbital cellulitis. Prompt initiation of intravenous antibiotics is mandatory and can prevent surgical procedures even in cases with incipient abscesses.

Point-of-Care Ultrasound Findings in a Case of Orbital Cellulitis: A Case Report.

BACKGROUND: Ophthalmologic complaints are common in the emergency department. The utility of point-of-care ultrasound (POCUS) as an accessible, noninvasive modality to evaluate ocular pathology is of great value-particularly in settings where resources are limited or where ophthalmologic consultation may not be readily available. CASE REPORT: A 21-year-old woman presented to the emergency department with periorbital edema, erythema, and drainage that was worsening despite topical and oral antimicrobial therapy. Mild proptosis was present on examination. POCUS was performed to investigate her symptoms further. A modified ocular ultrasound revealed prominence and edema of the retro-orbital soft tissue with echogenic fat, consistent with the diagnosis of orbital cellulitis. These findings were corroborated with computed tomography imaging. Why Should an Emergency Physician Be Aware of This?: Few reports describe the utility of POCUS in evaluating patients for orbital cellulitis. This case emphasizes the value of POCUS in assessing patients presenting to the emergency department with ocular complaints and demonstrates ultrasound-specific findings that may lead the clinician toward the diagnosis of orbital cellulitis. © 2021 Elsevier Inc.

The effect of point-of-care ultrasound on length of stay in the emergency department in children with neck swelling.

BACKGROUND: Ultrasound is the imaging modality of choice in children presenting to the emergency department (ED) with soft tissue neck swelling. Point of care ultrasound (POCUS) has good accuracy when compared to comprehensive radiology department ultrasound (RADUS). POCUS could potentially improve ED length of stay (LOS) by improving efficiency. We aimed to evaluate the LOS of pediatric patients seen in ED with soft tissue neck swelling who received POCUS compared to RADUS. We determined unscheduled 30-day return visit rates in both groups as a balancing measure. METHODS: We performed a retrospective review of the electronic medical record for our cross-sectional study of discharged patients ≤21 years of age who had a neck ultrasound performed by a credentialed POCUS physician or by the radiology department between July 2014 and January 2020. We included patients who had both POCUS and RADUS in the POCUS group. We compared median ED LOS in both groups using the Mann Whitney U test and proportion of unscheduled return visits to the ED in both groups using odds ratio and 95% CI. RESULTS: There were 925 patients: 76 with only POCUS, 6 with POCUS and RADUS, and 843 with only RADUS performed. Median LOS in the POCUS group was 68.5 min (IQR 38.3120.3) versus 154.0 min (IQR 111.0, 211.0) in the RADUS group (p < 0.001). Return visit overall was 7.6%: 13.2% in the POCUS group versus 7.1% in the RADUS group (p = 0.07). CONCLUSION: Pediatric patients evaluated in the ED for soft tissue neck swelling had a shorter LOS with POCUS than with RADUS without a statistically significant increase in 30-day return visits. We suggest a "POCUS First" approach to the care of these patients.

Point of Care Ultrasound Use by Associate Providers for Differentiating Abscess Versus Cellulitis Skin and Soft Tissue Infection in the Emergency Department.

BACKGROUND: Skin and soft tissue infections (SSTIs) are a common complaint in the ambulatory setting and pose a significant burden on the health care system. OBJECTIVES: We sought to determine the accuracy of ultrasound for detecting soft tissue abscesses by emergency medicine associate providers (APs). METHODS: This was a prospective observational study of adult patients with suspected SSTI in the emergency department of a rural tertiary care academic medical center. The AP performed and interpreted point-of-care ultrasound (POCUS) of the suspected infected area. Ultrasound images and interpretation were reviewed by the attending emergency physician with either rejection or agreement of the image interpretation, diagnosis, and management. If incision and drainage was performed, presence or absence of purulent drainage was recorded. RESULTS: Sixty-four patients with suspected SSTI were enrolled: 29 had POCUS-proven abscesses and 33 had cellulitis; 2 were excluded. AP clinical evaluation alone for identifying abscess revealed sensitivity of 92.3 (74.9-99.1), specificity of 67.7 (49.5-82.6), positive predictive value of 68.6 (57.0-78.2), and negative predictive value of 92.0 (81.4-100). The use of POCUS by APs in addition to clinical examination demonstrated sensitivity of 96.2 (80.4-99.9), specificity of 93.9 (79.8-99.3), positive predictive value of 92.6 (76.5-98.0), and negative predictive value of 96.9 (81.9-99.5). p values were <0.05 for test characteristics. Ultrasound results changed SSTI management decisions in 10 of 62 (16.1%) patients, with the most common change being a new incision and drainage or needle aspiration. Agreement of the POCUS interpretation between APs and attending physicians was 96.8% with a κ of 0.94 (0.85-1.00). CONCLUSION: With modest training, APs can successfully use POCUS to identify abscesses in patients in the emergency department with SSTIs. POCUS increases the ability to rule in the diagnosis and changes management in a clinically relevant number of patients with SSTIs.

Increased risk of malignancy for patients older than 40 years with appendicitis and an appendix wider than 10 mm on computed tomography scan: A post hoc analysis of an EAST multicenter study.

BACKGROUND: The incidence of underlying malignancy in appendicitis ranges between 0.5% and 1.7%. We sought to identify the subset of patients with appendicitis who are at increased risk of appendiceal malignancy. METHODS: Using the Eastern Association for the Surgery of Trauma Multicenter Study of the Treatment of Appendicitis in America: Acute, Perforated, and Gangrenous database, we included all patients from 28 centers undergoing immediate, delayed, or interval appendectomy between 2017 and 2018. Univariate then multivariable analyses were performed to compare patients with and without malignancy and to identify independent demographic, clinical, laboratory, and/or radiological predictors of malignancy. Akaike information criteria for regression models were used to evaluate goodness of fit. RESULTS: A total of 3,293 patients were included. The median age was 38 (27-53) years, and 46.5% were female patients. On pathology, 48 (1.5%) had an underlying malignancy (adenocarcinoma [60.4%], neuroendocrine [37.5%], and lymphoma [2.1%]). Patients with malignancy were older (56 [34.5-67] vs 37 [27-52] years, P < .001), had longer duration of symptoms before presentation (36-41 vs 18-23 hours, P = .03), and were more likely to have a phlegmon on imaging (6.3% vs 1.3%, P = .03). Multivariable analyses showed that an enlarged appendiceal diameter was independently associated with malignancy (odds ratio = 1.06, 95% confidence interval = 1.01-1.12; P = .01). The incidence of malignancy in patients >40 years with an appendiceal diameter >10 mm on computed tomography was 2.95% compared with 0.97% in patients ≤40 years old with appendiceal diameter ≤10 mm. The corresponding risk ratio for that population was 3.03 (95% confidence interval: 1.24-7.42; P = .02). CONCLUSION: The combination of age >40 and an appendiceal diameter >10 mm is associated with a greater than 3-fold increased risk of malignancy in patients presenting with appendicitis.

Advantages of otorhinolaryngologist performed transcervical ultrasonography in the management of peritonsillar abscess.

OBJECTIVES: Peritonsillar abscess (PTA) is a very common infection, in particular in pediatric and adolescent population. A distinction between peritonsillar cellulitis and abscess should be made to determine the appropriate treatment. Nonetheless, the difference cannot always be made on physical examination alone and often requires imaging by computed tomography (CT). Radiation exposure as well as the cost and waiting time question the use of CT in this pathology. We present our experience in the use of Transcutaneous Cervical Ultrasonography for the diagnosis and management of peritonsillar abscess in the adult population. STUDY DESIGN: Clinical-prospective. METHODS: Adult patients were evaluated for suspicion of PTA. Clinical findings were documented and all patients underwent a Transcutaneous Cervical Ultrasonography performed by a second otorhinolaryngology specialist well versed in Ultrasonography without knowing the clinical history, details of the physical examination, or the suspected side. Ultrasonography findings were later compared with the clinical examination and outcome of the medical or surgical management. RESULTS: Eight adult patients (range 18-53 year-old) were enrolled in the study. Six of them, had, ultrasonography findings compatible with a peritonsillar liquid collection underwent surgical drainage that confirmed and drained an abscess. On two patients, the ultrasonography images described an aspect of peritonsillar cellulitis that was managed conservatively and showed a favorable remission. No complications during stay or side effects or intolerance to the ultrasound were recorded. CONCLUSION: Transcutaneous Cervical ultrasonography is a fast, useful tool, better tolerated than the intra-oral ultrasonography in diagnosing PTA. It avoids all irradiation exposure is much cheaper and the waiting time is shorter. Worth noting, is the richness of information pertaining the anatomy, vessels and abscess location and extension, for the surgeon performing the exam just prior to surgery. The efficiency and training of otorhinolaryngology specialists with this technique shows numerous promising benefits and deserves to be further developed.

Imaging and Laboratory Workup for Hand Infections.

Hand infections can lead to significant morbidity if not treated promptly. Most of these infections, such as abscesses, tenosynovitis, cellulitis, and necrotizing fasciitis, can be diagnosed clinically. Laboratory values, such as white blood cell count, erythrocyte sedimentation rate, C-reactive protein, and recently, procalcitonin and interleukin-6, are helpful in supporting the diagnosis and trending disease progression. Radiographs should be obtained in all cases of infection. Ultrasound is a dynamic study that can provide quick evaluation of deeper structures but is operator dependent. Computed tomographic and MRI studies are useful for evaluating deep space or bony infections and preoperative surgical planning.

Point-of-Care Ultrasonography.

Point-of-care ultrasonography (POCUS) is performed by a physician at the bedside and is standard practice in obstetric, emergency, and musculoskeletal medicine. When compared with formal sonography, POCUS is equivalent in screening for abdominal aortic aneurysm and as accurate in diagnosing deep venous thrombosis. POCUS has high accuracy for diagnosing pneumonia and detecting acute decompensated heart failure but is less accurate than computed tomography for identifying pulmonary embolism. POCUS confirmation of intrauterine pregnancy rules out an ectopic pregnancy. In the third trimester of high-risk pregnancies, umbilical artery Doppler ultrasonography can improve perinatal outcomes. Musculoskeletal POCUS is used to diagnose and guide treatment of many joint and soft tissue conditions. It is as accurate as magnetic resonance imaging in the diagnosis of complete rotator cuff tears. Ultrasound guidance improves outcomes in the placement of central venous catheters and fluid drainage from body cavities and lumbar punctures. Ultrasonography can reduce the use of CT for diagnosis of appendicitis; however, negative scan results do not rule out disease. POCUS can accurately diagnose and rule out gallbladder pathology, and is effective for diagnosing urolithiasis. Focused cardiac ultrasonography can detect pericardial effusion and decreased systolic function, but is less accurate than lung ultrasonography at diagnosing acute heart failure. Limited evidence demonstrates a benefit of diagnosing testicular and gynecologic conditions. The American College of Emergency Physicians, the American Institute of Ultrasound in Medicine, the Society for Academic Emergency Medicine, the American College of Radiology, and others offer POCUS training. Training standards for POCUS have been defined for residency programs but are less established for credentialing.

Bacterial Flora in the Genital Area of Patients with Lower Limb Lymphedema.

Background: Patients with lymphedema, especially those having genital lymphangiectasia, experience repeated cellulitis; however, the causative bacteria are not detected in most cases. In this study, we investigated the composition of genital bacterial flora in patients with lower limb lymphedema to appropriately treat or prevent repeated cellulitis in these patients. Methods and Results: We examined 47 women with lower limb lymphedema. The average age was 58.4 (range 36-80) years. We performed indocyanine green (ICG) lymphography to confirm the presence of genital lymphedema. For each patient, we swab the skin in the genital area. The swabs were applied to aerobic agar plates, incubated, and evaluated to assess bacterial colonization and resistance to antibiotics. We numbered the patients who held the antibiotic-resistant bacteria, especially methicillin-resistant Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus, and extended spectrum ß-lactamase-producing Enterobacteriaceae. Among the 47 patients enrolled, 30 patients (63.8%) had a history of cellulitis accompanied by lymphedema and 31 patients (66.0%) had genital lymphedema diagnosed by ICG lymphography. Among 47 patients, 43 (91.5%) had at least one bacterial strain. Coryneform bacterial species were most commonly detected in 19 patients. Of 29 patients with a history of cellulitis, 9 had antibiotic-resistant bacteria (31.0%). In contrast, of 18 patients with no history of cellulitis, only 2 had antibiotic-resistant bacteria (11.1%) (p = 0.12). Conclusions: The percentage of patients with drug-resistant bacteria was higher among those with a history of cellulitis than among those without it.