Cannonball appearance,a tricky yet underrated imaging manifestation of COVID-19

Emergency Radiology - Spreading swiftly across the borders and over the seas, severe acute respiratory syndrome–related coronavirus-2 (SARS-COV-2), as causative pathogen of coronavirus...     

Inherited disorders of the IL-12-IFN-γ axis in patients with disseminated BCG infection

Disseminated BCG infection is a rare complication of vaccination that occurs in patients with impaired immunity. In recent years, a series of inherited disorders of the IL-12-IFN- axis have been described that predispose affected individuals to disseminated disease caused by BCG, environmental Mycobacteria, and non-typhoidal Salmonella. The routine immunological work-up of these patients is normal and the diagnosis requires specific investigation of the IL-12-IFN- circuit. We report here the first two such patients originating from and living in Iran. The first child is two years old and suffers from complete IFN- receptor 2 deficiency and disseminated BCG infection. He is currently in clinical remission thanks to prolonged multiple antibiotic therapy. The other, a 28-year-old adult, suffers from IL-12p40 deficiency and presented with disseminated BCG infection followed by recurrent episodes of systemic salmonellosis. He is now doing well. A third patient of Iranian descent, living in North America, was reported elsewhere to suffer from IL-12R1 deficiency. These three patients thus indicate that various inherited defects of the IL-12-IFN- circuit can be found in Iranian people. In conclusion we recommend to consider the disorders of the IL-12-IFN- circuit in all patients with severe BCG infection, disseminated environmental mycobacterial disease, or systemic non-typhoidal salmonellosis, regardless of their ethnic origin and country of residence.     

Acute Retinal Necrosis after Herpetic Encephalitis

PURPOSE: To report a case of unilateral acute retinal necrosis after herpetic encephalitis CASE REPORT: A young man was referred with a chief complaint of blurred vision and pain of the left eye 1 month after herpetic encephalitis in the left frontotemporal lobe. The patient had multiple foci of retinitis in the retinal periphery associated with vitritis, blot retinal hemorrhage and retinal arteriolitis. The impression of acute retinal necrosis was confirmed by polymerase chain reaction of aqueous humor by detecting herpes simplex virus type 2; therefore, the patient received intravenous acyclovir. CONCLUSION: Herpetic encephalitis may be a risk factor for acute retinal necrosis. The virus may reach the eye by the trans-axonal route. Prophylaxis with acyclovir may be necessary after herpetic encephalitis to prevent acute retinal necrosis.     

Evaluation of T cell immune responses in multi-drug-resistant tuberculosis (MDR-TB) patients to Mycobacterium tuberculosis total lipid antigens

Mycobacterium tuberculosis lipid antigens produce significant T cell responses in healthy tuberculin reactor [purified protein derivative (PPD-positive] individuals. In the present study, proliferation and interferon (IFN)-gamma/interleukin (IL)-4 responses were analysed to M. tuberculosis total lipid antigens in T lymphocytes from 25 patients with multi-drug-resistant tuberculosis (MDR-TB). The obtained results were compared with those of 30 asymptomatic healthy PPD-positive and 30 healthy tuberculin skin test negative (PPD-negative) subjects. Peripheral blood mononuclear cells (PBMCs) and T cells (CD4(+) and CD8(+)) were stimulated using autologous immature dendritic cells. Proliferation responses were assessed using 3-{4,5-dimethylthiazol-2-yl}-2,5 diphenyl tetrazolium bromide (MTT). IFN-gamma/IL-4 concentrations in the supernatant of the CD4(+) and CD8(+)T cells were measured by enzyme-linked immunosorbent assay. Proliferation assay showed that the peripheral blood mononuclear cells and CD4(+) T cells from the MDR-TB patients responded significantly less to the M. tuberculosis total lipid antigens than to the CD4(+) T cells in the PPD-positive subjects. Total lipid antigen-specific proliferative responses in the CD8(+) T cells from the MDR-TB patients were minimally detected and the responses were similar to those of the PPD-positive subjects. IFN-gamma production by the CD4(+) T cells stimulated by total lipid antigens from the MDR-TB patients was decreased significantly compared with the PPD-positive individuals, whereas IL-4 production in the patients was elevated. IFN-gamma and IL-4 production in the CD8(+) T cells of the MDR-TB patients was similar to those of the PPD-positive subjects. In conclusion, it is suggested that stimulated CD4(+) T cells by M. tuberculosis total lipid antigens may be shifted to T helper 2 responses in MDR-TB patients.     

Instability of IS6110 patterns in multidrug-resistant strains of Mycobacterium tuberculosis

The stability of IS6110 restriction fragment length polymorphism (RFLP) pattern was determined in 31 isolates from patients with multidrug-resistant tuberculosis (MDR-TB). These patients were in actual chains of transmission and they referred to the National Institute of Tuberculosis and Lung Diseases, Tehran, Iran. Susceptibility testing against first- and second-line drugs were performed by the proportional method on Lowenstein-Jensen culture media. Thereafter, DNA fingerprinting by IS6110 with direct repeat (DR) region as a probe was performed by standard protocols. The rate of IS6110 changes was 16%, although, no variation was found in the DR region, in a time-span of 1-63 months. The strains with unstable IS6110 patterns were resistant to all drugs tested, and the majority of them (60%) were collected from HIV-positive patients. The results demonstrated that for a reliable interpretation of strain typing, it is better to use an additional marker along with IS6110 RFLP.