Point-of-care ultrasound differentiates pyomyositis from cellulitis

Skin, Soft Tissue, and Musculoskeletal Ultrasound

Point-of-care ultrasound may be used to assist in the diagnosis of skin, soft tissue, and musculoskeletal concerns in the emergency department. Frequently, linear or curvilinear probes are used to perform these studies and ultrasound may be used to assist in common emergency department procedures related to these conditions.

Arthritis or an Adjacent Fascial Response? A Case Report of Combined Pyomyositis and Aseptic Arthritis

Pyomyositis, accompanied by aseptic arthritis, has been previously documented in several publications. However, none of the authors in the mentioned case reports offered a pathophysiological explanation for this unusual phenomenon or proposed a treatment protocol. We present a case of a healthy, 70-year-old male who was presented to the emergency department 4 days after tripping over a pile of wooden planks and getting stabbed by a nail to his thigh. The right thigh was swollen. Unproportional pain was produced by a light touch to the thigh. A laboratory test and a CT scan were obtained. The working diagnosis was pyomyositis of the thigh and septic arthritis of the ipsilateral knee. The patient underwent urgent debridement and irrigation of his right thigh. An arthroscopic knee lavage was performed as well. Intraoperative cultures from the thigh revealed the growth of Streptococcus pyogenes and Staphylococcus aureus. Cultures from synovial fluid were sterile; thus, septic arthritis was very unlikely. The source of the knee effusion might have been an aseptic inflammatory response due to the proximity of the thigh infection. Anatomically, the quadriceps muscle inserts on the patella, and its tendon fuses with the knee capsule, creating a direct fascial track from the thigh to the knee. The inflammatory response surrounding the infection may have followed this track, creating a domino effect, affecting adjacent capillaries within the joint capsule, and causing plasma leakage into the synovial space, leading to joint effusion. Our suggested treatment is addressing the primary infection with antibiotics and considering adding anti-inflammatory therapy, given our suspicion that this process has an inflammatory component.

High-Resolution Ultrasound for Complications of Botulinum Toxin Use: A Case Series and Literature Review

Botulinum toxin (BTX) has revolutionized both aesthetic and therapeutic medicine by selectively inhibiting acetylcholine release at the neuromuscular junction, inducing localized muscle relaxation. However, its use can be associated with various complications. As a diagnostic modality, high-resolution ultrasound can better characterize these complications. Here, we present four clinical cases of complications associated with the application of BTX, along with their corresponding ultrasonographic findings. In this study, cases were selected randomly, irrespective of the timing of BTX injections, to illustrate a spectrum of complications observed in clinical practice. Despite its benefits, BTX can have adverse effects ranging from mild to severe, including aesthetic and functional complications, such as hematoma, ptosis, facial asymmetry, nodules, or pseudoaneurysm. High-resolution ultrasound emerges as a crucial tool in the multidisciplinary management of these complications, allowing for accurate evaluation and effective therapeutic guidance.

Point-of-Care Ultrasound Identifies Pyomyositis Secondary to Intramuscular Testosterone Injection: Report of Two Cases

BACKGROUND

Intramuscular (i.m.) injections are a commonly utilized route for medication delivery. Intramuscular-associated soft tissue infections are rare and can include pyomyositis and i.m. abscess. Intramuscular testosterone injections have not been previously implicated in causing pyomyositis. Point-of-care ultrasound is an important bedside tool that can identify pyomyositis and differentiate this infection from more common entities such as cellulitis.

CASE REPORTS

We present two cases of i.m. testosterone-associated pyomyositis. In both cases, the physical examination features were consistent with simple cellulitis. However, point-of-care ultrasound evaluation revealed changes consistent with pyomyositis in each case. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although uncommon, i.m. injections such as testosterone carry a risk of soft tissue infection. As demonstrated in the above cases, ultrasound can be helpful in making the differentiation between simple cellulitis and pyomyositis. The emergency physician should be cognizant of this complication of therapeutic i.m. injections, as well as the diagnostic efficacy of point-of-care ultrasound in evaluating the extent and location of the soft tissue infection.

Emergency physician-performed bedside ultrasound of pyomyositis

Point-of-care ultrasound (POCUS) is an indispensable tool for emergency physicians in the rapid bedside diagnosis of skin and soft tissue infections. The utility of POCUS for the differentiation of cellulitis and subcutaneous abscess is well established; however, there is a paucity of studies highlighting POCUS as a first-line imaging approach for pyomyositis, an uncommon skeletal muscle infection and/or intramuscular abscess formation requiring emergent diagnosis. This report describes a case in which emergency physician-performed POCUS led to the early detection and timely management of pyomyositis in the emergency department.

Purulent infectious myositis (formerly tropical pyomyositis)

Purulent infectious myositis (PIM), formerly known as tropical pyomyositis, is a pyogenic infection of skeletal muscles. Staphylococcus aureus, a normal human skin inhabitant, is the main pathogen involved, but multiple other microorganisms have been implicated. Although usually a progressive febrile disease with pain in the affected muscle(s), severe, life-threatening forms have been described, especially in immunosuppressed patients and children. PIM may elude early diagnosis given the lack of overlying skin changes. Hence, high index of suspicion followed by imaging modalities (ultrasonography when superficial and computed tomography or magnetic resonance imaging with contrast when deep) help confirm the diagnosis. Treatment requires combination of percutaneous or open surgical drainage along with antimicrobial therapy guided by culture results. The rising incidence of cases due to methicillin-resistant Staphylococcus aureus (MRSA) strains, makes the inclusion of vancomycin be recommended. This paper reviews PIM highlighting its global distribution, causative agents, predisposing factors, management, and potential complications.

Sternal Fracture Complicated by a Subcutaneous Abscess in a 5-Year-Old Boy and Diagnosed Using Point-of-Care Ultrasound

BACKGROUND

Although fractures of the sternum are rare in young children, owing to the compliance of the chest wall, these fractures are still possible and require thorough examination. We present a case that emphasizes the usefulness of point-of-care ultrasound in the diagnosis of a pediatric sternal fracture complicated by a subcutaneous abscess.

CASE REPORT

A 5-year-old boy presented with tenderness of the sternum, with diffuse swelling extending bilaterally to the anterior chest wall. Ultrasound imaging identified irregular alignment of the sternum with a subcutaneous abscess and swirling of purulent material within the abscess in the fracture area. These findings were confirmed on enhanced chest computed tomography and had not been visible at the time of the first evaluation 6 days prior. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Our case demonstrates the usefulness of point-of-care ultrasound for the diagnosis and appropriate management of a sternal fracture complicated by a subcutaneous abscess in a young child. As ultrasound imaging is easy to perform at the bedside, it is useful for examining pediatric patients with swelling of the anterior chest and local tenderness of the sternum to rule out a sternal fracture, even if these fractures are deemed to be uncommon in children.

Sonographic appearance of pyomyositis of the sternocleidomastoid muscle: A case report

Pyomyositis in the neck has rarely been described. We present the sonographic findings in a case of pyomyositis of the sternocleidomastoid muscle. A 62-year-old man with poorly controlled diabetes presented with an induration of the neck and fever. On gray-scale sonography, a part of the sternocleidomastoid muscle appeared swollen and contained irregularly shaped hypoechoic areas. Power Doppler imaging showed increased vascularity in the muscle. Sonographic-guided aspiration confirmed abscesses in the sternocleidomastoid muscle. Surgical drainage was successfully performed along with antibiotic treatment. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:520-523, 2017.