Disseminated tuberculosis associated with reactive arthritis of Poncet in an immunocompetent patient

Dactylitis and Ungual Tuberculosis: An Atypical Presentation of the Disease

Introduction

Tuberculosis is a common infection caused by Mycobacterium tuberculosis in developing countries. Among the extrapulmonary forms of tuberculosis, cutaneous tuberculosis is rare, and even dermatologists are less familiar with its ungual manifestations.

Case Presentation

We present an exuberant case of ungual tuberculosis in a patient with no personal or family history of immunosuppression, which is the first manifestation of the disseminated form of the disease.

Conclusion

In our patient, the initial manifestation was related to the nail, probably originating from the progression of bone TB focus, which further progressed with respiratory symptoms and involvement of other organs. We believe this is the first case in which the ungual presentation allowed the diagnosis of disseminated tuberculosis.

Reactive Arthritis Update: Spotlight on New and Rare Infectious Agents Implicated as Pathogens

Purpose of Review

This article presents a comprehensive narrative review of reactive arthritis (ReA) with focus on articles published between 2018 and 2020. We discuss the entire spectrum of microbial agents known to be the main causative agents of ReA, those reported to be rare infective agents, and those reported to be new candidates causing the disease. The discussion is set within the context of changing disease terminology, definition, and classification over time. Further, we include reports that present at least a hint of effective antimicrobial therapy for ReA as documented in case reports or in double-blind controlled studies. Additional information is included on microbial products detected in the joint, as well as on the positivity of HLA-B27.

Recent Findings

Recent reports of ReA cover several rare causative microorganism such as Neisseria meningitides, Clostridium difficile, Escherichia coli, Hafnia alvei, Blastocytosis, Giardia lamblia, Cryptosporidium, Cyclospora cayetanensis, Entamoeba histolytica/dispar, Strongyloides stercoralis, β-haemolytic Streptococci, Mycobacterium tuberculosis, Mycoplasma pneumoniae, Mycobacterium bovis bacillus Calmette-Guerin, and Rickettsia rickettsii. The most prominent new infectious agents implicated as causative in ReA are Staphylococcus lugdunensis, placenta- and umbilical cord–derived Wharton’s jelly, Rothia mucilaginosa, and most importantly the SARS-CoV-2 virus.

Summary

In view of the increasingly large spectrum of causative agents, diagnostic consideration for the disease must include the entire panel of post-infectious arthritides termed ReA. Diagnostic procedures cannot be restricted to the well-known HLA-B27-associated group of ReA, but must also cover the large number of rare forms of arthritis following infections and vaccinations, as well as those elicited by the newly identified members of the ReA group summarized herein. Inclusion of these newly identified etiologic agents must necessitate increased research into the pathogenic mechanisms variously involved, which will engender important insights for treatment and management of ReA.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11926-021-01018-6.