Subcutaneous Sweet syndrome associated with disseminated nontuberculous mycobacterial infection leading to the diagnosis of adult-onset immunodeficiency

Insights Into the Pathogenesis of Sweet's Syndrome

Sweet's syndrome, also known as Acute Febrile Neutrophilic Dermatosis, is a rare inflammatory condition. It is considered to be the prototype disease of neutrophilic dermatoses, and presents with acute onset dermal neutrophilic lesions, leukocytosis, and pyrexia. Several variants have been described both clinically and histopathologically. Classifications include classic Sweet's syndrome, malignancy associated, and drug induced. The cellular and molecular mechanisms involved in Sweet's syndrome have been difficult to elucidate due to the large variety of conditions leading to a common clinical presentation. The exact pathogenesis of Sweet's syndrome is unclear; however, new discoveries have shed light on the role of inflammatory signaling, disease induction, and relationship with malignancy. These findings include an improved understanding of inflammasome activation, malignant transformation into dermal infiltrating neutrophils, and genetic contributions. Continued investigations into effective treatments and targeted therapy will benefit patients and improve our molecular understanding of inflammatory diseases, including Sweet's syndrome.

Dot enzyme-linked immunosorbent assay strip as a screening tool for detection of autoantibody to interferon gamma in sera of suspected cases of adult-onset immunodeficiency

BACKGROUND

Being able to detect the presence of autoantibodies to interferon (IFN)-γ in serum is essential for evaluating patients with suspected adult-onset immunodeficiency (AOID) with unusual intracellular infections. Most reported patients with AOID have been Asian, although the exact prevalence of this illness is unknown. To date, no standard assay exists to detect autoantibodies to IFN-γ. An easy-to-use, low-cost assay that can be performed in any laboratory would be a valuable tool for clinical management of AOID, as well as better reveal its prevalence.

METHODS

Our experimental study exploited a dot enzyme-linked immunosorbent assay (Dot-ELISA) strip to detect autoantibodies to IFN-γ. Sera from 66 HIV-negative patients having autoantibodies to IFN-γ as determined by indirect ELISA were tested.

RESULTS

Dot enzyme-linked immunosorbent assay was sensitive (100%) and specific (94.5%), with a positive predictive value of 97.6% and a negative predictive value of 100%.

CONCLUSION

This simple method provides prompt qualitative results that can be read visually and used in facilities with limited testing capabilities.

Patient ethnicity and causative species determine the manifestations of anti-interferon-gamma autoantibody-associated nontuberculous mycobacterial disease: a review

Nontuberculous mycobacteria (NTM) infections involving anti-interferon-gamma (IFN-γ)-neutralizing autoantibodies have been described in previously immunocompetent adults. To investigate the factors underlying various disease manifestations, we reviewed 35 articles published between January 2004 and November 2016 and identified 111 NTM patients with anti-IFN-γ autoantibodies. Rapidly growing mycobacteria (RGM) accounted for 53% of the isolated species. RGM were predominant among the NTM species isolated from Thai (73%), Chinese (58%) and Filipino (56%) patients, whereas M. avium complex (MAC) was predominant among Japanese (58%) and non-Asian (80%) patients. The commonly involved organs included the lymph nodes (79%), bones/joints (34%) and lungs (32%). Compared with the patients with MAC, the patients with RGM had a higher incidence of lymph node lesions (P<0.05) and a lower incidence of bone/joint (P<0.01), lung (P<0.01), soft tissue (P<0.01), bronchus (P<0.01) and muscle (P<0.05) lesions. Clinical manifestations of NTM disease with anti-IFN-γ-neutralizing autoantibodies differ across ethnicities and NTM species.

Clinical features and outcomes of Sweet's syndrome associated with non-tuberculous mycobacterial infection and other associated diseases

Sweet's syndrome (SS) is associated with various diseases including non-tuberculous mycobacterial infection (NTM). Recent reports have shown that SS associated with NTM is increasing. Clinical features of SS associated with NTM may be different from SS associated with other associated diseases. The aim of the present study was to compare clinical parameters and treatment outcomes of SS associated with NTM and other associated diseases. Patients from January 2004 to April 2014 diagnosed with SS were retrospectively enrolled. Clinical variables were compared between SS patients with and without NTM infection. There were 51 SS patients during the study period; 36 patients (70.59%) had NTM. Clinical variables between the NTM and other associated diseases were comparable: age, sex, and pattern and locations of skin lesions. Five laboratory factors were significantly different between the groups including white blood cell counts (NTM 25 800 vs 12 850 cells/mm(3) ), lymphocyte percentages (13.0% vs 18.7%), monocytes (3.0% vs 7.2%), blood urea nitrogen (BUN) (11.7 vs 8.1 mg/dL) and serum creatinine (Cr) (1.0 vs 0.7 mg/dL). The presence of markedly high white blood cell counts, a low percentage of mononuclear cells and high BUN/Cr levels in SS may be a clinical clue to recognize the association with NTM infections; particularly in dissemination.