MRI and Sonography of the Knee in Acute Reactive Arthritis: An Observational Cohort Study.

INTRODUCTION: Reactive arthritis (ReA) is a unique subgroup of spondyloarthritis with acute presentation and tendency to develop chronicity. Magnetic resonance imaging (MRI) has enabled identification of sensitive markers of response to therapy. METHODS: A longitudinal pilot study of acute ReA with knee joint involvement satisfying the Braun's criteria was undertaken. Magnetic resonance imaging of the knee was assessed at baseline, and agreement with ultrasonography was assessed. Clinical details were recorded using a detailed and structured case record form. Patients were followed up, and MRI predictors of transition to chronic arthritis were looked for. RESULTS: In 25 patients with ReA, synovial thickening was the most common feature. Enthesitis was observed on MRI in 20%. Urethritis-related and HLA-B27-positive ReA had higher synovial thickening scores (p = 0.007). Agreement was poor between MRI and ultrasonography (synovial hypertrophy: k = 0.04). On follow-up, 34% (n = 7/21 for >12 months) continued to have active disease. None of the clinical or radiological features were predictive of chronicity. CONCLUSIONS: Posturethritis and B27-positive ReA was more severe than postenteritis ReA and RA on MRI. One third develop chronic disease on follow-up. Magnetic resonance imaging is superior to sonography, although baseline imaging is not predictive of chronicity. The results of this pilot exploratory study argue for larger studies on MRI in ReA.

Ultrasound liver elastography for the detection of liver fibrosis in patients with psoriasis and reactive arthritis on long-term methotrexate therapy: A cross-sectional study.

BACKGROUND: Long-term low-dose methotrexate therapy is associated with liver fibrosis. Although liver biopsy is the gold standard for detecting fibrosis, it is an invasive procedure associated with morbidity and mortality risks. Hence noninvasive imaging techniques such as transient elastography (TE) and shear wave elastography (SWE) have been studied to measure liver stiffness. AIMS: To assess the utility of TE and SWE in detecting fibrosis in patients with psoriasis and reactive arthritis on long-term methotrexate therapy. METHODS: A cross-sectional prospective study was undertaken on 54 patients with psoriasis and reactive arthritis who had received ≥1.5 g of methotrexate. Various clinical and biochemical [fibrosis 4 index (FIB4), aspartate-transaminase-to-platelet ratio index (APRI)] parameters were calculated and liver stiffness measurement (LSM) was done with TE and SWE. The degree of steatosis was measured using controlled attenuation parameter (CAP). Liver biopsy was done when indicated and was interpreted by a pathologist blinded to clinical and imaging results. RESULTS: Fifty four patients with a mean age of 40.3 years and a male-to-female ratio of 5:1 were included. The mean cumulative methotrexate dose was 3.04 g. The median FIB4, APRI, and gamma-glutamyl transpeptidase-to-platelet ratio values were 0.75, 0.23, and 0.15, respectively. The median LSM for TE and SWE was 5.3 and 7.32 kPa, respectively. SWE and TE showed a weak positive correlation (r = 0.26, P = 0.053). The mean CAP was 217 dB/m (area under the receiver operating characteristic = 0.70). In the 19 of 26 cases whose liver biopsies could be assessed, only 4 (21%) showed F1 fibrosis (Ishak staging). The median LSM on SWE was significantly higher in patients with a cumulative methotrexate dose ≥ 4 g when compared with those with a dose <4 g (9.85 vs 7.1, P = 0.02). Other parameters did not correlate with TE and SWE. LIMITATIONS: The small sample size and the low number of cases with significant fibrosis on histopathology were the major limitations of this study. CONCLUSION: Histologically detectable LF is uncommon in patients with psoriasis and reactive arthritis on long-term methotrexate therapy. Both TE and SWE are good at detecting the absence of fibrosis in these patients. In our study, SWE and TE values did not correlate with clinical, biochemical, or histopathological parameters.

Induction of HLA-B27-Associated Reactive Arthritis After a Wharton's Jelly "Stem Cell" Injection.

Orthobiologic injections are an emerging treatment option for musculoskeletal conditions. Allogenic gestational tissue-derived products, including umbilical cord-derived Wharton's jelly, are among the available options. These tissues are currently being harvested and sold by companies as an off-the-shelf "stem cell" injection for conditions such as back pain and osteoarthritis. Despite documented infections from similar umbilical cord derivatives, "stem cell clinics" continue to use them. Here, we report the first documented case of HLA-B27-associated reactive arthritis induced by a Wharton's jelly stem cell injection. A 36-yr-old man was injected with Wharton's jelly for low back pain and within 24 hours developed fevers, chills, polyarthritis, and enthesitis. Infectious disease work-up was negative. Inflammatory markers were elevated and his HLA-B27 antigen was positive. Initial treatment included methylprednisolone and sulfasalazine. This case highlights the unknown dangers of these allogenic injections and physicians should remain cautious about their use until further study and regulation can ensure patient safety.

Reactive arthritis induced by active extra-articular tuberculosis: A case report.

RATIONALE: Rare cases of reactive arthritis induced by active extra-articular tuberculosis (Poncet disease) have been reported. Complete response to antitubercular treatment and evidence of active extra-articular tuberculosis are the most important clinical features of Poncet disease. We report the case of successfully treated a patient with reactive arthritis induced by active extra-articular tuberculosis with a TNF inhibitor after sufficient antitubercular treatment. PATIENT CONCERNS: A 56-year-old Japanese man was admitted to our department with polyarthralgia, low back pain, and high fever. The results of rheumatoid factor, anti-citrullinated protein antibody, human leukocyte antigen B27, and the assays for the detection of infections (with an exception of T-SPOT.TB) were all negative. Fluoro-deoxy-D-glucose-positron emission tomography with CT (PET/CT) showed moderate uptake in the right cervical, right supraclavicular, mediastinal, and abdominal lymph nodes. As magnetic resonance imaging and power Doppler ultrasonography showed peripheral inflammation (tendinitis, tenosynovitis, ligamentitis, and enthesitis in the limbs). DIAGNOSIS: A diagnosis of tuberculous lymphadenitis was eventually established on the basis of lymph node biopsy results. There was no evidence of a bacterial infection including acid-fast bacteria in his joints, and the symptoms of polyarthralgia and low back pain were improved but not completely resolved with NSAID therapy; in addition, a diagnosis of reactive arthritis induced by active extraarticular tuberculosis was made. INTERVENTIONS: The patient experienced persistent peripheral inflammation despite antitubercular treatment for more than nine months and was then successfully treated with a tumor necrosis factor inhibitor (adalimumab 40 mg every 2 weeks). OUTCOMES: Finally, the patient responded to the treatment and has been in remission for over 4 months as of this writing. LESSONS: In patients who present with symptoms associated with spondyloarthritis, it is important to distinguish between classic reactive arthritis and reactive arthritis induced by extra-articular tuberculosis infection. Introduction of biological agents should be carefully considered in settings where reactive arthritis induced by active extra-articular tuberculosis shows progression to chronicity despite sufficient antitubercular treatment.

Acute onset of psoriatic spondyloarthritis as a new manifestation of post-streptococcal reactive arthritis: a case series.

Streptococcus is well associated with a myriad of inflammatory diseases. Among others, this bacterium is linked to the triggering of psoriasis and to post-streptococcal reactive arthritis (PSRA), an arthritis which is typically confined to peripheral joints. Three patients who developed acute psoriatic spondyloarthritis (SpA) following a recent streptococcal infection are described in this article. We searched the existing literature for cases of axial involvement in PSRA and reviewed the association between streptococcal infection and psoriasis or psoriatic arthritis )PsA). In all patients, psoriatic SpA occurred within 7-10 days of a confirmed streptococcal infection. The main presenting syndrome was inflammatory back pain with evidence of acute axial spondyloarthritis on magnetic resonance imaging. One patient had guttate psoriasis, the second patient developed pustular psoriasis, and the third patient had exacerbation of pustular palmoplantar psoriasis. Two patients required treatment with tumor necrosis factor alpha (TNF-α) blockers. Axial involvement in PSRA is very rare. A potential association of streptococcal infection and development of PsA has been explored in several articles. However, to the best of our knowledge, acute psoriatic SpA as a manifestation of PSRA has yet to be described. Acute psoriatic SpA should be considered in the differential diagnosis of new-onset inflammatory back pain followed by psoriasis in young adults who had a recent throat infection. KEY POINTS: • Our case series describes three cases of acute psoriatic spondyloarthritis that occurred within 7--10 days of a confirmed streptococcal infection and progressed to full blown chronic disease. • Acute psoriatic spondyloarthritis as a manifestation of post streptococcal reactive arthritis should be considered in the differential diagnosis of new onset inflammatory back pain followed by psoriasis in young adults who had a recent throat infection.

Are we overcalling sacroiliitis on MRI? Differential diagnosis that every rheumatologist should know - Part I.

Diagnosing early spondyloarthritis remains a challenge in routine practice, especially in its axial (SpA) form. Magnetic resonance imaging (MRI) is capable of detecting early bone marrow edema (BME) in the sacroiliac joints (SIJs), a key criterion for the diagnosis of active SpA according to the "imaging arm" of the Assessment of Spondyloarthritis International Society (ASAS) classification. However, despite MRI having superior reliability compared to radiographs and being recognized as a crucial imaging biomarker of SpA, it has several limitations, including its limited specificity and sensitivity. Based on the established literature, there is currently an "overcall" of sacroiliitis on MRIs. In this setting, differential diagnoses and their imaging features come into play. In this two-part article, we will review both the imaging features that constitute a "positive" MRI in SpA and the most common differential diagnoses. In order to understand the pathophysiology of sacroiliitis and the spectrum of developing lesions, one needs to be familiar with the complex SIJs anatomy, both on radiographs and on cross-sectional imaging studies (particularly MRI). As such, in the first part of this article, we provide a brief background on anatomy and different imaging modalities used in this clinical setting and we review the imaging criteria for a "positive" MRI study of sacroiliitis in adults (imaging arm of the ASAS classification).

Reactive arthritis secondary to Hafnia alvei enterocolitis.

Diagnosis of postenteritic reactive arthritis (ReA) is a challenge and might have a broad range of differential diagnoses. A 50-year-old man was referred to our attention because of persistent inflammatory low back pain and asymmetric oligoarthritis. The clinical history was positive for diarrhoea in the previous 3 months. Inflammatory bowel disease, Whipple and celiac diseases were carefully excluded. In addition, serology, stool cultures, biopsies from the upper gastrointestinal tract yielded negative results for infections. A presumptive diagnosis of ReA was done and a non-steroidal anti-inflammatory drug trial prescribed. Persistence of symptoms prompted us for a second look of the colon. Biopsy collected from the terminal ileum were cultured and surprisingly colonies of Hafnia alvei, a rod-shaped Enterobacteriaceae, were detected. Treatment with ciprofloxacin leads to fast symptoms resolution. Although enterocolitis from H. alvei has been rarely reported, the culture of intestinal specimens might be recommended in the work-up of patients with suspected postenteritic ReA.

Acute severe monarthritis: a rare manifestation of scrub typhus.

Scrub typhus caused by Orientia tsutsugamushi is an important cause for fever of unknown origin in endemic areas including India. The vasculitis associated with the disease leads to a variety of clinical manifestations. However, the joint involvement is quite rare and not reported in children. We present severe arthritis of hip joint associated with scrub typhus causing a diagnostic and management challenges in a 4-year-old girl.

Hypertrophic osteoarthropathy mimicking a reactive arthritis: a case report and review of the literature.

BACKGROUND: Hypertrophic osteoarthropathy (HOA) is a syndrome characterized by abnormal proliferation of skin and periosteal tissues of the extremities. It can be a rare hereditary disease (pachydermoperiostosis) or can be secondary to various diseases, though mostly lung malignancies. Here, we report an unusual clinical presentation of HOA. CASE PRESENTATION: A 77-year-old man presented with fever, diarrhea, and an oligoarthritis involving the left knee and the ankles. Since left knee synovial fluid aspiration revealed an aseptic synovitis and Clostridium Difficile toxin was detectable in stool samples, a reactive arthritis secondary to a Clostridium Difficile induced colitis was initially suspected. However, the presence of a worsened digital clubbing and the lack of a good clinical response to steroid therapy led us to perform a radionuclide bone scanning, which revealed HOA. This turned out to be associated with a lepidic predominant lung adenocarcinoma, which was clinically and radiologically difficult to distinguish from a relapse of pneumonia. CONCLUSION: Consistent with the literature, HOA tends to have a variable clinical presentation, mimicking that of various rheumatic diseases. This clinical case shows that HOA can present as a presumptive acute reactive arthritis, and it highlights the importance of patient's follow-up in the differential diagnosis of inflammatory arthritis, especially when a worsened digital clubbing is present.

Poststreptococcal reactive arthritis in Japan.

Reactive arthritis after Group A streptococcal infection (poststreptococcal reactive arthritis: PSRA) that does not meet the Jones criteria for acute rheumatic fever (ARF) has been reported as a new entity for over a decade. In Japan there are few reports of PSRA. We encountered four children with arthritis accompanied with Group A streptococcal infection in our department. We investigated our cases and the recent Japanese literature. Japanese cases of PSRA are frequently accompanied with uveitis and erythema nodosum, and tonsillectomy resolved their symptoms in some cases. There were overlap cases between ARF, juvenile idiopathic arthritis, and PSRA.

Strongly positive anti-CCP antibodies in patients with sacroiliitis or reactive arthritis post-E. coli infection: A mini case-series based review.

We report here on four cases of patients with strongly positive anti-citrullinated cyclic peptides (anti-CCP) antibodies and clinical features of seronegative spondyloarthritis (SpA) and reactive arthritis. The four patients had various clinical presentations: one had an initial diagnosis of seropositive rheumatoid arthritis (RA) with involvement of the sacroiliac joints (similar to previous reports of the association of two diseases); one had a clinical picture of reactive arthritis following an episode of an Escherichia coli positive urinary tract infection; and two had asymmetrical sacroiliitis (SII), but no evidence of peripheral joint involvement (never reported before). In all cases, high titers of anti-CCP antibodies were found. We present a comparison of the clinical manifestations, radiographic features and treatment regimens of these cases. Our report supports previous literature data of possible overlap existing between RA and SpA, but also presents for the first time the association of high titers of anti-CCP antibodies with SII and reactive arthritis in patients with no peripheral small joint involvement.

Imaging of Inflammatory Arthritis in Adults: Status and Perspectives on the Use of Radiographs, Ultrasound, and MRI.

The term inflammatory arthritis encompasses a variety of conditions featuring synovial inflammation as a defining characteristic, with resultant local tissue damage occurring over time. These arthritides often share overlapping clinical and imaging characteristics, although the pattern of joint involvement, specific appearance of pathologic changes, and associated findings often allow imaging-based differentiation or individual arthritides.

Poncet's disease (tubercular rheumatism) with primary involvement of the foot - A case report.

We present a rare case with primary tubercular involvement of the foot, accomapanied by a reactionary (aseptic) effusion in the knee. The diagnosis was delayed due to unusual presentation and also because of failure to elicit a detailed history. Incision and drainage of the foot abscess and antitubercular drug therapy resulted in satisfactory control of tubercular infection. Polyarticular presentation may not always signify active tubercular focus in every joint; it may reflect reactive synovitis known as Poncet's disease, which resolves with multidrug antitubercular therapy.A multidispilinary approach should be adopted and chest physicians, rheumatologists and orthopaedic surgeons should work in close association to correctly diagnose and treatthis condition.

Reiter's syndrome--disease of young men-- analysis of 312 patients.

INTRODUCTION: Reiter's syndrome is reactive arthritis occurring after acute urogenital (urethritis, cervicitis) or enterocolitis infections. The associated ophthalmological and/or mucocutaneous changes are full clinical manifestations of this disease. This paper was aimed at analyzing clinical and radiological characteristics and findings of possible etiological factors and protocol for Reiter's syndrome therapy. MATERIAL AND METHODS: Of 312 patients included in the study, 279 were men and 33 were women, the ratio between them being 8.5:1. The disease was diagnosed based on clinical evidence of two basic characteristics of Reiter's syndrome: arthritis preceded by acute urogenital or enteral infection. RESULTS: Urogenital and enterocolitic form of disease was found in 242 (77.5%) and 52 (16.5%) patients, respectively; whereas the initial cause was not discovered in 18 patients (6%). Three or two main signs of Reiter's syndrome were present in approximately the same number of patients (41.7% and 44.2%), whereas all four signs of disease were present in 14.1% of the patients. Acute or sub-acute form was present in 40.5%, while recurrent and chronic disease was diagnosed in 31% and 28.5% of the patients, respectively. The most frequent clinical manifestation of this disease was on the locomotor system as asymmetrical oligoarthritis localized in lower extremities, present in 69.4% of the patients. Chlamydia trachomatis was found in the synovial fluid in 54% of patients (20/37), ureaplasma or mycoplasma was isolated in the synovial tissue of 73.1% of patients (30/41) and in the peripheral blood mononuclear cells in 93.2% of patients (41/44). Human leukocyte antigen B27 was present in 83.3% of patients. CONCLUSION: Reiter's syndrome is a multisystem disease, predominantly occurring in human leukocyte antigen B27 positive young males. The fact that the causative agents are found in the synovial membrane or synovial fluid is indicative of infectious rather than reactive arthritis.