MRI of musculoskeletal extraspinal tuberculosis

Tuberculosis of ischial tuberosity as a rare cause of gluteal pain: A case series of 9 patients with review of literature

BACKGROUND

Osteo-articular Mycobacterium tuberculosis infection of the ischial tuberosity is a rare cause of gluteal pain.

METHODS

A retrospective clinico-radiological review of nine patients with Mycobacterium tuberculosis infection of the ischial tuberosity was undertaken. The spectrum of presenting features, diagnostic challenges, radiological findings with particular emphasis on Magnetic resonance imaging (MRI) and clinical course was reviewed.

RESULTS

All the 9 patients (5 male: 4 female) aged between 8 and 50 years of age (mean 15.3 years) developed insidious onset of buttock pain over a period of weeks to months with difficulty in walking. Microbiological and/or histopathological confirmation of Mycobacterium tuberculosis infection was undertaken in all cases. Complementary MRI revealed diffuse bone marrow signal hypointense or isointense on T1-weighted and hyperintense on T2-weighted and STIR images. MRI was able to provide anatomic details of soft tissue lesions and extensions. MRI illustrated the sinus tract in one patient. Ultrasound imaging allowed diagnostic and therapeutic management of in 3 patients.

CONCLUSION

Tuberculosis of ischial tuberosity can be a rare cause of gluteal pain. Delay in diagnosis could be due to an indolent natural history, unusual presentation and clinical features. A high index of suspicion especially in endemic areas with complementary imaging and microbiological or histopathological confirmation of Mycobacterium tuberculosis infection is necessary for definitive diagnosis. Targeted treatment under the umbrella of Anti-Tubercular Therapy is crucial in achieving successful clinical outcome.

[Infectious myositis]

Infectious myositis is a rare condition that can be caused by bacteria, viruses, parasites or fungi. Muscle pain or weakness are symptoms shared by all type of myositis. Diagnosis is made on clinical presentation: fever and poor general state is found in bacterial myositis, diffuse muscle pain with flu-like symptoms in viral causes, eosinophilia and a tropical travel history can be related to parasitic etiology, and immunocompromising condition suggests fungal infection. Rhabdomyolysis, leukocytosis and elevated C-reactive protein are common. Imaging (computed tomography or magnetic resonance imaging) can be useful to detect which muscle is affected. The causative organism can be identified on blood cultures, skeletal muscle biopsy, serology or any other pathogen specific test. Treatment depends on the causative organism. Open surgical or imaging-guided drainage is usually necessary in bacterial myositis.

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.

[MRI appearance of tuberculosis of the tibia in children: about a case]

La localisation osseuse isolée de la tuberculose est peu fréquente et survient surtout chez les adultes jeunes immunodéprimés. Elle peut simuler une infection à germe banal au début ou une atteinte tumorale lorsque l’évolution est chronique. Les auteurs rapportent le cas d'une patiente de 15 ans sans antécédent particulier ayant présenté une tuméfaction indurée et indolore du tiers supérieur de la jambe d'évolution chronique. Les explorations radiologiques conventionnelles ont permis d'objectiver une lésion lytique tibiale métaphysaire supérieure avec une réaction périostée. L’IRM a précisé une rupture corticale et une extension aux parties molles sous la forme d'une collection liquidienne avec une paroi épaisse, se rehaussant intensément après injection de gadolinium. Une biopsie chirurgicale avec analyse histologique a permis de retenir le diagnostic d’ostéite tuberculeuse. Ce cas clinique souligne l'intérêt de l’IRM dans l'exploration des pathologies musculosquelettiques.

Osteoraticular Tuberculosis-Brief Review of Clinical Morphological and Therapeutic Profiles

Osteoarticular tuberculosis (OATB) is a rare form of tuberculosis (TB) whose incidence rose significantly nowadays especially in the underdeveloped countries. The main risk factors predisposing to this new challenge for the medical system are the Human Immunodeficiency Virus (HIV) epidemic, the migration from TB endemic areas and the development of drug and multidrug-resistant strains of Mycobacterium tuberculosis (Mt). The disease affects both genders and any age group although the distribution depending on gender is controversial and that depending on age has a bimodal pattern. In most cases the initial focus is elsewhere in the organism and the most frequent pathway of dissemination is lympho-haematogenous. The clinical picture includes local symptoms as pain, tenderness and limitation of motion, with some particularities depending on the segment of the osteoarticular system involved, sometimes accompanying systemic symptoms specific for TB and other specific clinical signs as cold abscesses and sinuses. The radiographic features are not specific, CT demonstrates abnormalities earlier than plain radiography and MRI is superior to plain radiographs in showing the extent of extraskeletal involvement. Both CT and MRI can be used in patient follow-up to evaluate responses to therapy. TBhas been reported in all bones of the body, the various sites including the spine (most often involved) and extraspinal sites (arthritis, osteomyelitis and tenosynovitis and bursitis). Two basic types of disease patterns could be present: the granular type (most often in adults) and the caseous exudative type (most often in children) one of which being predominant. The algorithm of diagnosis includes several steps of which detection of Mt is the gold standard. The actual treatment is primarily medical, consisting of antituberculosis chemotherapy (ATT), surgical interventions being warranted only for selected cases. It is essential that clinicians know and refresh their knowledge about manifestations of OATB.

Magnetic resonance imaging features of complications following hip replacement: A pictorial review

Hip replacement surgery helps millions of people worldwide walk painlessly each year. With increasing life spans and decreased clinical threshold for surgery, this number will continue to rise. With the increase in the number of surgeries and the longevity of implants, the need for early and prompt diagnosis of complications is also rising. This essay underlines the fact that magnetic resonance imaging on a 1.5T scanner with specialized metal artefact reduction sequences is a viable technique to image the post-arthroplasty hip and has vast potential in the prompt and early diagnosis of complications in these patients.

Tuberculous pyomyositis: a re-emerging entity of many faces

Tuberculosis (TB) has become a global concern due to its increasing incidence, particularly in immunocompromised patients, closely following the migratory patterns of populations. TB pyomyositis is a rare extrapulmonary manifestation of TB. Its clinical presentation varies and requires a high degree of suspicion for early diagnosis. We present three patients diagnosed with TB pyomyositis: a 46-year-old man with dermatomyositis (DM) and hepatitis B who presented with fever, muscle weakness, and an abscess at the right proximal arm; a 71-year-old immunocompetent male, with a past medical history of tuberculous lymphadenopathy in childhood, who presented with a 2-month history of fever and pain at the right thigh, and a 44-year-old woman with systemic lupus erythematosus (SLE) on prednisone and methotrexate who presented with skin eruption at her thighs mimicking lupus panniculitis. In all three patients, Mycobacterium tuberculosis was identified as the causative agent. The lack of specific signs, the false negative tuberculin skin test in some cases, and the unfamiliarity of many clinicians with this entity can cause diagnostic delays. Prompt diagnosis requires a high index of suspicion especially in immunocompromised patients with fever.

[Primary tuberculous pyomyositis in an immunocompetent patient: report of a case]

L'atteinte du muscle strié au cours de la tuberculose chez un sujet immunodéprimé ou à partir de l'extension d'un foyer ostéo-articulaire de voisinage est rare mais bien connue. Toutefois, l'atteinte primitive est exceptionnelle ainsi que celle chez un sujet immunocompétent. L'imagerie par résonnance magnétique (IRM) est d'un grand apport pour le diagnostic avec une excellente sensibilité. Nous rapportons un cas de pyomyosite tuberculeuse primitive du mollet chez une patiente non immunodéprimé tout en précisant l'apport de l'IRM.

Tuberculous pyomyositis: a rare but serious diagnosis

Tuberculous pyomyositis is a rare clinical entity with serious consequences if a diagnosis is not established early. A 53-year-old female with a past medical history of sarcoidosis and pulmonary fibrosis presented from an outside hospital with persistent fevers and a rash. She had been hospitalized multiple times at an outside hospital without any improvement in her symptoms. On examination, she was noted to have a large area of left upper lower extremity (LUE) tenderness with superimposed erythema. Laboratory data revealed a white blood cell count of 22,300. Computed tomography (CT) scans of the LUE, chest, and left lower extremity (LLE) showed multiple intramuscular abscesses in those regions without evidence of osteomyelitis. Subsequent drainage of the abscesses and resulting cultures revealed Mycobacterium tuberculosis. The patient was started on therapy with rifampin, isoniazid, pyrazinamide, and ethambutol. However, the patient developed hepatitis on these agents and subsequently went into septic shock with multiorgan failure. Care was eventually withdrawn as a result of a poor prognosis. This case illustrates the severe consequences of TB pyomyositis if not diagnosed promptly. While tuberculosis is uncommon in the United States, it should be an important consideration in the differential diagnosis of immunocompromised patients.

Imaging features of pediatric musculoskeletal tuberculosis

Tuberculosis (TB) is widely prevalent in developing nations and has recently made a comeback in industrialized countries, with the rise in immunocompromized patients. Musculoskeletal TB in children presents a diagnostic challenge because it is difficult to recognize in the early stages of the disease, and imaging features mimic other entities. The clinical onset is insidious, with an indolent course and a resultant late presentation. It leads to significant morbidity; a delay in diagnosis can cause potentially serious neurological complications and bone and joint destruction. Conventional radiographs are the initial imaging modality and US, CT and MRI are used in conjunction to better delineate the disease extent and morphology. Radiologists should be familiar with the spectrum of imaging features of TB, including plain radiographs and MRI, and aid the clinician in making an early diagnosis. Aspiration or biopsy with examination for acid-fast bacillus and histological evaluation is required to confirm the diagnosis.

Tuberculous extensor tenosynovitis of the hand

Tuberculous tenosynovitis is a rare manifestation of extrapulmonary tuberculosis (Tb), especially if solely the dorsal hand compartment is affected. In this report, we present the medical history of an immuno-competent 32-year-old man presented with a painful swelling of the right dorsal wrist. Initial inflammation onset had occurred 6 months before he consulted our service, resulting in consultation of several physicians and extensive diagnostic procedures without gaining a specific diagnosis. Finally, after extensive diagnostic tests, a tenosynovectomy was performed and tuberculosis-induced extensor tenosynovitis was detected. The diagnosis was established by positive histology, repeated specific PCR and T-SPOT.TB. Tuberculous tenosynovitis can easily be overlooked as a cause of chronic tenosynovitis particularly in immunocompetent young people lacking any risk factors.

Evaluation of adequacy of short-course chemotherapy for extraspinal osteoarticular tuberculosis using 99mTc ciprofloxacin scan

In the evidence-based medicine era, objective treatment guidelines have been laid down for pulmonary tuberculosis, but the same is not true for osteoarticular tuberculosis. This has led to demands for standardising the treatment protocol and to a lack of consensus between doctors regarding the composition and duration of treatment. Twenty-five patients with extraspinal osteoarticular tuberculosis were evaluated prospectively. Following the diagnosis, patients were given standard directly observed treatment short course (DOTS) regimen and were monitored for disease activity at zero, three and six months with the help of technetium-99m-labelled ciprofloxacin ((99m)Tc) scan. Tracer activity at the site was recorded and compared on sequential scans. Clinical and radiological profile of all the patients were also recorded at regular intervals and compared. All 25 cases had a positive (99m)Tc bone scan initially. Four patients (16%) converted to negative scans at three months, whereas the remaining 21 patients (84%) showed negative scans at six months. The end of six months therapy also coincided with resolution of clinical and radiological parameters in all cases. In conclusion, (99m)Tc scan is a promising tool for monitoring drug response in osteoarticular tuberculosis; however, due to the small sample size, studies with a large number of patients might be of help.

Imaging features of extraaxial musculoskeletal tuberculosis

Tuberculosis (TB) continues to be a public health problem in both developing and industrialized countries. TB can involve pulmonary as well as extrapulmonary sites. The musculoskeletal system is involved in 1–3% of patients with tuberculosis. Although musculoskeletal TB has become uncommon in the Western world, it remains a huge problem in Asia, Africa, and many developing countries. Tuberculous spondylitis is the most common form of musculoskeletal TB and accounts for approximately 50% of cases. Extraspinal musculoskeletal TB shows a predilection for large joints (hip and knee) and para-articular areas; isolated soft tissue TB is extremely rare. Early diagnosis and prompt treatment are mandatory to prevent serious destruction of joints and skeletal deformity. However, due to the nonspecific and often indolent clinical presentation, the diagnosis may be delayed. Radiological assessment is often the first step in the diagnostic workup of patients with musculoskeletal TB and further investigations are decided by the findings on radiography. Both the radiologist and the clinician should be aware of the possibility of this diagnosis. In this manuscript we review the imaging features of extraspinal bone, joint, and soft tissue TB.

Use of technetium(99m)-ciprofloxacin scan in Pott's spine to assess the disease activity

PURPOSE

The World Health Organisation has declared tuberculosis (TB) a global emergency and spinal tuberculosis is one of the most common forms. There is still controversy regarding optimum duration of treatment in osteoarticular tuberculosis due to the lack of well-defined criteria for the end point of treatment. Emergence of multi drug resistant tuberculosis, primarily due to use of poor drug regimens, further illustrates the need of newer and more effective diagnostic methods, particularly in developing countries.

METHODS

This prospective clinical study to evaluate the role of technetium ((99m)Tc)-ciprofloxacin scan as a tool to assess disease activity involved in 15 cases of TB spine with a mean age of 32.2 years (range 21-72). Following a clinico-radiological diagnosis, all patients were treated with standard anti tubercular treatment and a scan was done at zero, three and six months of treatment with tracer activity being recorded and compared in sequential scans along with a parallel evaluation of clinical and radiological profile at regular intervals.

RESULTS

Out of 15 cases, nine had an initially positive bone scan. Two patients (22%) converted to negative scans at three months, whereas the remaining seven (78%) turned negative at six months. The end of six months treatment was also accompanied by clinico-radiological resolution in all cases.

CONCLUSION

In conclusion, technetium ((99m)Tc)-ciprofloxacin scan could be a promising tool for monitoring disease activity in selected cases of tuberculosis spine as an alternative for therapeutic drug monitoring; however, due to the small sample size, studies with a large number of patients might be of help in defining these cases in a better way.

Tuberculous pyomyositis of forearm muscles

Tuberculous pyomyositis is a rare entity reported in literature. The presented case reports the occurrence of such a lesion in forearm muscles, without any bony involvement. The ambiguity in its diagnosis led to inadequate management by the primary care physician. Clinical suspicion, positive tuberculin test, culture of acid-fast bacilli, 'effective drainage', and timely anti-tubercular chemotherapy ultimately resulted in a good clinical recovery. This case has been presented to increase the awareness about the existence of such an entity in clinical practice, thereby influencing its workup and the possible modes of management.

Tuberculous bicipitoradial bursitis: a case report

An 76-year-old man with an indolent soft tissue mass on the volar aspect of the left elbow was referred to our institution with a diagnosis of a soft tissue tumor. He had a history of lung tuberculosis since the age of 30. The mass was adjacent to the biceps brachi tendon. It demonstrated homogeneous low-signal intensity on T1-weighted magnetic resonance (MR) images and heterogeneous relatively high signal intensity with scattered low and high signal intensity areas on T2-weighted MR images. An excision was performed after needle biopsy with presumptive diagnosis of bicipitoradial bursitis. The histological specimen revealed an epithelioid cell granuloma with central necrosis. While the occurrence of tuberculous bicipitoradial bursitis has never been reported, this case demonstrates that it can be considered to be among the causes of a cystic lesion around the elbow joint.

Imaging of osteomyelitis: current concepts

Osteomyelitis frequently requires more than one imaging technique for an accurate diagnosis. Conventional radiography still remains the first imaging modality. MRI and nuclear medicine are the most sensitive and specific methods for the detection of osteomyelitis. MRI provides more accurate information regarding the extent of the infectious process. Ultrasound represents a noninvasive method to evaluate the involved soft tissues and cortical bone and may provide guidance for diagnostic or therapeutic aspiration, drainage, or tissue biopsy. CT scan can be a useful method to detect early osseous erosion and to document the presence of sequestra. PET and SPECT are highly accurate techniques for the evaluation of chronic osteomyelitis, allowing differentiation from soft tissue infection.

Imaging of extraspinal musculoskeletal tuberculosis

Tuberculosis (TB) is still a major cause of significant morbidity and mortality despite universal availability of effective chemotherapy. The emergence of multidrug-resistant mycobacteria along with a worldwide increase in HIV infection has led to a recent surge in the number of patients with TB. TB involves both pulmonary and extrapulmonary sites. Tuberculous spondylitis is the most common form of musculoskeletal TB and accounts for approximately 50% of cases. Extraspinal musculoskeletal TB is among the least common manifestations of TB. It shows a predilection for joints and para-articular areas while isolated soft tissue TB occurs extremely rare. A non-specific, often indolent clinical presentation in conjunction with its low prevalence constitutes obstacles for diagnosis. The differential diagnosis of extraspinal musculoskeletal TB consists of degenerative processes, inflammatory and infectious conditions, primary neoplasms, and metastatic lesions. Early diagnosis and treatment is of utmost importance to prevent serious joint and bone destruction. Radiological assessment of patients with musculoskeletal TB is often the key to adequate diagnosis and early treatment. The purpose of this manuscript is to review the imaging features of extraspinal musculoskeletal TB and to focus on the magnetic resonance imaging (MRI) characteristics of this pathology.

Tuberculous arthritis of the appendicular skeleton: MR imaging appearances

Tuberculosis [TB] of the appendicular skeleton is an uncommon infection caused by the tuberculous bacilli and constitutes only 1-3% of all tuberculosis infections. MR imaging features of tuberculous arthritis include bone marrow oedema, cortical erosions, synovitis, joint effusion, tenosynovitis, soft tissue collections, and myositis. These imaging features are at times non-specific, but in the correct clinical context help in diagnosis of tuberculosis. We present the various pathological manifestations of TB arthritis involving the different joints of appendicular skeleton and discuss their MR imaging appearances.

Imaging features of musculoskeletal tuberculosis

The purpose of this article is to review the imaging characteristics of musculoskeletal tuberculosis. Skeletal tuberculosis represents one-third of all cases of tuberculosis occurring in extrapulmonary sites. Hematogenous spread from a distant focus elsewhere in the body is the cornerstone in the understanding of imaging features of musculoskeletal tuberculosis. The most common presentations are tuberculous spondylitis, arthritis, osteomyelitis, and soft tissue involvement. The diagnostic value of the different imaging techniques, which include conventional radiography, CT, and MR imaging, are emphasized. Whereas conventional radiography is the mainstay in the diagnosis of tuberculous arthritis and osteomyelitis, MR imaging may detect associated bone marrow and soft tissue abnormalities. MR imaging is generally accepted as the imaging modality of choice for diagnosis, demonstration of the extent of the disease of tuberculous spondylitis, and soft tissue tuberculosis. Moreover, it may be very helpful in the differential diagnosis with pyogenic spondylodiscitis, as it may easily demonstrate anterior corner destruction, the relative preservation of the intervertebral disk, multilevel involvement with or without skip lesions, and a large soft tissue abscess, as these are all arguments in favor of a tuberculous spondylitis. On the other hand, CT is still superior in the demonstration of calcifications, which are found in chronic tuberculous abscesses.

Imaging of osteomyelitis and musculoskeletal soft tissue infections: current concepts

The diagnostic imaging of osteomyelitis can require the confluence of multiple imaging technologies. Conventional radiography should always be the first imaging modality. Sonography is most useful in the diagnosis of fluid collections in a joint or in the extra-articular soft tissues but is not useful for evaluating presence of osseous infection. CT scan can be a useful method to detect early osseous erosion and to document the presence of sequestrum, foreign body, or gas formation but generally is less sensitive than other modalities for the detection of bone infection. Nuclear medicine and MRI are the most sensitive and most specific imaging modalities for the detection of osteomyelitis. Nuclear medicine is particularly useful in identifying multifocal involvement, which is common in children. MRI provides more accurate information of the local extent of the soft tissues and possible soft tissue abscess in patients with musculoskeletal infection.

Tuberculosis pyomyosits of the soleus muscle in a fifteen-year-old boy

Skeletal muscle infection caused by Mycobacterium tuberculosis is rare and usually caused by invasion from adjacent structures. We describe a 15-year-old male youth with tuberculous right inguinal lymphadenitis and right calf swelling who had tuberculous pyomyositis of the soleus, probably resulting from hematogenous seeding. Tuberculosis should be suspected as the cause of pyomyositis, especially if present elsewhere.