Tuberculous pyomyositis: a re-emerging entity of many faces

Diagnosis of multiple tuberculous muscle abscesses in a patient with systemic lupus erythematosus by metagenomic next-generation sequencing- a case report and literature review

BACKGROUND

Early diagnosis of muscular tuberculosis (TB) without coexistent active skeletal involvement is often challenging because the disease is very rare and its clinical manifestation is nonspecific and misleading. To raise the awareness and emphasize early diagnosis of muscular TB, we present a case of multiple tuberculous muscle abscesses in a systemic lupus erythematosus (SLE) female, but without pulmonary tuberculosis (PTB), in order to increase awareness of and stress the need of early detection of muscular TB.

CASE PRESENTATION

A 44-year-old woman with a 6-year history of SLE who had been treated with methylprednisolone for a long time complained of erythema on her trunk and extremities for five months, along with edema and myalgia for two months, and fever for one month. The patient was first misdiagnosed as SLE overlap dermatomyositis. However, an ultrasound-guided drainage of muscle abscesses revealed positive acid-fast staining combined with positive deoxyribonucleic acid fragment of Mycobacterium tuberculosis using metagenomic next-generation sequencing (mNGS). The patient was cured and released following standard anti-tuberculosis medication, local puncture drainage, and an intravitreal injection of streptomycin. Literature search found only 19 cases of tuberculous muscle abscesses occurring in the extremities reported from 1999 to 2023.

CONCLUSIONS

Extrapulmonary TB with predominantly muscle involvement is rare and with no specific clinical presentation. Muscular tuberculosis may be disdiagnosed for dermatomyositis due to the high muscle enzyme levels, delaying diagnosis and treatment. mNGS technology is helpful in the early and rapid diagnosis of muscular TB. On the basis of traditional anti-tuberculosis treatment, an ultrasound-guided percutaneous puncture drainage and intracavitary injection of streptomycin for the treatment of tuberculous muscle abscess is easy to operate, safe and effective, which is worthy of clinical popularization and application.

Pyomyositis involving the scapular muscles: A case series

Pyomyositis or tropical pyomyositis is an uncommon infection of skeletal muscle that may be primary or secondary. Primary type has bacterial aetiology, and Staphylococcus aureus is associated in most cases. The diagnosis requires high index of suspicion and careful assessment of radiological investigations. Diagnosis often requires magnetic resonance imaging (MRI) for better delineation of the disease process, associated site involvement and exclusion of related conditions. Evacuation of pus coupled with appropriate antibiotic therapy is the mainstay and curative in most cases. Caution, however, is required due to increased morbidity, protracted course of recovery and mortality in few cases. The association with comorbidities including immunocompromised status compounds the problem. We describe our experience with this condition in a series of five cases (four male and one female) with diverse involvement of scapular muscle. All cases had primary pyomyositis except one case secondary to shoulder joint tuberculosis. Right side was involved in three and left in two cases. Infraspinatus was commonly involved, and one case had extensive involvement around scapula. All cases were managed by one or multiple aspiration, except one managed with open surgical drainage. The outcome was good in all cases with no recurrence or complication noted in their respective follow-up. Primary care centres may play important role in the early diagnosis of this condition with clinical evaluation and judicious use of imaging. Cases with severe involvement or those requiring advanced procedures may be referred to higher centres as per the requirement. Most of the times, timely diagnosis, antibiotic therapy and drainage of the pus is required and may also be performed in the primary care level through a standard protocol.

Isolated Tuberculous Myositis: A Systematic Review and Multicenter Cases

Objective

To investigate the clinical features and associated underlying conditions of isolated tuberculous myositis (ITBM), a rare extrapulmonary tuberculosis (TB).

Methods

A systematic literature search and a multicenter survey were performed using a triangulation strategy. Data from the identified ITBM cases were extracted and analyzed to determine the underlying conditions, clinical presentations, treatments, and outcomes.

Results

Based on the systematic review, we identified 58 ITBM, including 9 pediatric, cases in the literature published from 1981 to 2021 25 (43.1%) immunocompromised and 33 (56.9%) non-immunocompromised patients. Immunocompromised cases had a significant shorter symptom duration (median 30.0 vs. 75.0 days) and a higher prevalence of multilocular involvement (20.8% vs. 0%). Among 24 immunocompromised adult patients, dermatomyositis/polymyositis (DM/PM; n=10, 41.7%) were the most common underlying diseases in adults with ITBM identified in the systematic review. Over the past 20 years, 11 Korean adults with ITBM were identified in the multicenter survey. Of 7 immunocompromised cases, two (28.6%) were DM/PM patients. TB death rate of immunocompromised patients was 0.0% and 5/23 (21.7%) in the pediatric and adult ITBM cases identified in the systematic review, respectively, and 3/7 (42.9%) in survey-identified ITBM cases.

Conclusion

ITBM has a unique clinical presentation including fever, tenderness, local swelling, overlying erythema, abscess formation and was associated with a grave outcome, especially in immunocompromised hosts. DM/PM was a highly prevalent underlying disease in both systematic review-identified and survey-identified immunocompromised ITBM patients.

Severe thoracic pyomyositis in a patient with systemic lupus erythematosus

Pyomyositis may mimic deep vein thrombosis and be misdiagnosed in patients with systemic lupus erythematosus (SLE). We report here on patient with SLE with severe thoracic pyomyositis presented with right upper arm swelling and fever. The patient fully recovered after a serial surgical debridement and antibiotic therapy. Pyomyositis, as well as deep vein thrombosis, should be considered during the differential diagnosis of patients with SLE experiencing fever and unilateral limb oedema. CT and identification of causal pathogens are crucial in the diagnosis of pyomyositis. Early effective antibiotic treatment as well as surgical intervention can together bring about a better outcome.

Discrimination between tuberculous and bacterial pyomyositis in magnetic resonance features

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Discriminating imaging features between bacterial and tuberculous pyomyositis.

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T2 high signal intensity at abscess wall can predict for bacterial pyomyositis.

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Abscess wall character on imaging of bacterial muscle infection.

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Magnetic resonance imaging between bacterial and tuberculous muscle infection.

Purpose

The purpose of this study was to assess the differences of magnetic resonance features between tuberculous and bacterial pyomyositis.

Method

This is a retrospective study of patients with bacterial and tuberculous pyomyositis. We excluded patients with pyomyositis caused by actinomycosis, non-tuberculous mycobacterium, fungi, unknown of causative organism, or inadequate imaging for analysis. Magnetic resonance imaging was independently reviewed by two radiologists.

Results

Of the 136 pyomyositis patients, 71 (52.2 %) patients had bacterial pyomyositis while 65 (47.8 %) patients had tuberculous pyomyositis. Seventy-seven patients (56.6 %) had intramuscular abscess. On multivariable analysis, bacterial pyomyositis was associated with diabetes mellitus (odds ratio [OR] 3.17, 95 % confidence interval [CI] 1.30–8.24) and bone marrow involvement (OR 5.02, 95 % CI 1.21–34.4). Spinal involvement had a significantly lower likelihood of bacterial pyomyositis (OR 0.25, 95 %CI 0.11–0.54). In patients with intramuscular abscess, diabetes mellitus and hyperintense on T2-weighted images at the abscess wall had a significantly higher likelihood of bacterial pyomyositis (OR 5.21, 95 %CI 1.33–25.42 and OR 5.34, 95 %CI 1.36–24.71, respectively), whereas spinal involvement had a significantly lower likelihood of bacterial pyomyositis (OR 0.09, 95 %CI 0.02–0.30).

Conclusions

Magnetic resonance imaging has modest accuracy for differentiation of tuberculous and bacterial pyomyositis. Diabetes mellitus and extraspinal pyomyositis were the predictors of bacterial pyomyositis. Presence of T2 hyperintense wall of intramuscular abscess was also the predictor of bacterial pyomyositis.

Abdominal rectus muscle pyomyositis: Report of a case and review of the literature

Pyomyositis is an uncommon primary bacterial infection of skeletal muscles, usually caused by Staphylococcus aureus. Predisposing factors for pyomyositis include immunodeficiency, trauma, injection drug use, concurrent infection and malnutrition. The diagnosis, staging of the disease and differential diagnosis are established by ultrasound, CT and MRI. Treatment involves surgical drainage and antibiotic therapy. We report a case of abdominal rectus muscle pyomyositis, which constitutes, as far as we know, the second reported in bibliography, while Prevotella disiens is firstly reported as causative agent.

Pyomyositis in a patient with systemic lupus erythaematosus and a review of the literature

Pyomyositis (PM) is a common masquerading disease that is frequently misdiagnosed. A concurrent state of immunodeficiency is observed in up to 75% of tropical PM cases. PM in systemic lupus erythaematosus (SLE) is a relatively rare disease. I report a case of PM that was caused byKlebsiella pneumoniaein a patient with SLE who presented with leg pain, fever and a lupus flare-up. The patient was correctly diagnosed using a CT scan. Immediate surgical drainage was performed, and empirical antibiotics were administered. The patient was discharged while in a recovering condition. The clinical features, the results of radiographic investigations and the management of PM in SLE are synopsised in this article to underscore the importance of considering this relatively rare disease during differential diagnosis in patients with SLE with muscle pain with or without fever. I also emphasise the need to exclude mycobacterial infection in patients with SLE with PM.

Tuberculous pyomyositis in an immunosuppressed patient

Tuberculous pyomyositis is a rare manifestation of extrapulmonary tuberculosis, most common in immunosuppressed patients, with clinical manifestations similar to pyomyositis of other etiologies, although with a lower age of presentation; notable risk factors include prior tuberculosis infection and pharmacological immunosuppression. Diagnosis depends on a high clinical suspicion of the infection in a susceptible population, given that microbiological isolation is often impossible. The response to treatment and prognosis are good. The case presented here is noteworthy given the rarity of this manifestation of tuberculosis and the slow response to first-line TB management in an HIV patient, despite susceptible microbiological isolation.