IL-17 and IFN-γ producing NK and γδ-T cells are preferentially expanded in synovial fluid of patients with reactive arthritis and undifferentiated spondyloarthritis.

The IL-17/1L-23 axis is important in the pathogenesis of spondyloarthropathy. Innate cells produce IL-17 in addition to Th17 cells. We studied the frequencies of natural killer (NK) (total, CD56bright, CD56dim, perforin+ and granzyme+), NK-T, γδ-T, and IFN-γ+, IL-17+ NK and γδ-T cells in peripheral blood (PB) and synovial fluid (SF) of ReA/uSpA patients. PB from 45 patients and paired SF from 39 patients were studied, together with PB from 18 healthy controls (HC). The frequency of γδ-T cells was decreased (p<0.05) while IL-17 producing NK and γδ-T cells were increased (p<0.05) in PB of patients as compared to HC. In SF, CD56bright NK cells were increased (p<0.001) but had reduced expression of perforin and granzyme (p<0.0001) as compared to PB. Frequency of IL-17+, IFN-γ+ NK and γδ-T cells was higher in SF as compared to PB (p<0.05). We suggest that innate cells by producing pro-inflammatory cytokines may contribute to pathogenesis.

Gangrene in Takayasu's arteritis: a report of two cases and review of literature.

Takayasu's arteritis (TA) is a granulomatous large vessel vasculitis more commonly seen in India. The vascular inflammation in TA results in stenoses of affected vessels. Usually this is a slow process with good collateral circulation; only rarely does critical limb ischemia result. We present two patients of TA who presented with gangrene of extremities, and review eight prior such patients reported in the literature. With appropriate diagnosis and treatment with oral corticosteroids and low-dose aspirin, none of our patients had recurrence at a mean follow-up of 3.8 ± 2.8 years. Although rare, TA can present with gangrene and rheumatologists need to be aware of this unusual but limb-threatening manifestation of TA to institute appropriate therapy in a timely manner.

Behcet's disease without oral ulcers presenting with erythema nodosum and deep venous thrombosis.

We present a young male with recurrent erythema nodosum and recent deep vein thrombosis with scrotal ulcers but no oral ulcers. He was diagnosed as having Behcet's disease (BD) and subsequently responded to immunosuppressants and anticoagulation. This case highlights that up to 2% patients with BD may not have oral ulcers. Timely institution of therapy in our patient resulted in a favorable outcome.

Refractory polymyositis undergoing remission following antitubercular therapy.

Opportunistic infections pose a significant problem in patients receiving immunosuppressive therapy for autoimmune diseases. We present a case of a woman with polymyositis refractory to high-dose steroid and methotrexate, as a consequence of which she developed miliary tuberculosis. Her myositis went into remission after initiation of antitubercular therapy, in spite of bringing down the intensity of immunosuppression. This is the first reported case of myositis undergoing remission after treating intercurrent infection, and illustrates the complex relationship between autoimmune disease and host response to infection.

Pulmonary co-infection with Nocardia and Aspergillus in a patient with adult-onset Still's disease receiving steroids and tacrolimus.

Patients on immunosuppression are at risk of unusual infections. We present a man diagnosed to have adult-onset Still's disease who, on high-dose oral steroid and tacrolimus, developed a cavitating pneumonia due to co-infection with Aspergillus flavus and Nocardia. Timely diagnosis and institution of appropriate therapy resulted in a favourable clinical outcome. Such co-infection in a patient receiving tacrolimus is rare in the published literature. This case serves to emphasise the need to be vigilant for unusual infections in patients who are immunosuppressed, either due to drugs or underlying disease condition.

Lepra reaction with lucio phenomenon mimicking cutaneous vasculitis.

Leprosy is a disease typically found in the tropics. Patients with leprosy can have varying presentation with constitutional symptoms, joint pains, skin nodules, and rarely a vasculitis-like picture with skin ulcers and neuropathy. We present a young lady who presented with the rare manifestation of skin infarcts mimicking cutaneous vasculitis, diagnosed on histopathology to have Lucio phenomenon on a background of lepromatous leprosy. With increasing migration and widespread use of biologic response modifiers, clinicians all over the world need to be aware of various presentations of leprosy as well as needing to keep an open mind while considering the differential diagnoses of vasculitis.