Disseminated Bacillus Calmette-Guérin infection: role of imaging in the evaluation of complications.

BACKGROUND: The Bacillus Calmette-Guerin (BCG) vaccine is generally used to prevent tuberculosis, particularly meningeal and miliary types, in childhood. This vaccine can rarely cause complications of varying severity, ranging from localized disease to a severe diffuse type known as disseminated BCG infection. Imaging modalities play an important role in the evaluation of different complications of disseminated BCG infection. This study aimed to assess and describe the imaging findings of disseminated BCG infection in order to help clinicians diagnose this life-threatening infection more accurately. METHODS: This retrospective study was performed on 44 hospitalized children diagnosed with disseminated BCG infection. The results of radiographs, sonography, computerized tomography (CT) scan and magnetic resonance imaging were compiled in a checklist and were then assessed by a radiology resident and a board-certificated radiologist. The radiological findings from various imaging modalities were presented descriptively and the frequency of different parameters was reported. RESULTS: Axillary lymphadenopathy at the vaccinated side was frequent and was often associated with abscesses. However, abscesses in other body regions were uncommon. The most common abdominal imaging findings were enlarged liver and spleen accompanied by multiple hypoechoic and hypodense nodules on ultrasound and CT scans, respectively. Furthermore, diffuse or multifocal pulmonary opacities were the most frequent findings on chest X-rays and CT scans. CONCLUSION: Characteristic imaging findings of disseminated BCG infection play a vital role in the early diagnosis of this infection. The study findings demonstrated the importance of radiological imaging in the diagnosis and evaluation of the complications of disseminated BCG infection.

Imaging Spectrum of Coronavirus Disease- 2019 Associated Rhino-Orbital-Cerebral Mucormycosis; From Sinonasal Inflammation to Intracranial Involvement.

RATIONALE AND OBJECTIVES: Rhino­Orbital­Cerebral Mucormycosis (ROCM) is a life-threatening opportunistic fungal infection, which mostly affects immunocompromised patients. There has been a notable rise in the incidence of ROCM during the COVID-19 outbreak. In this study we described imaging characteristics of ROCM in detail, from early sinonasal inflammation to late intracranial involvement. MATERIALS AND METHODS: In this retrospective study, Computed Tomography (CT) scan and Magnetic Resonance Imaging (MRI) of 48 patients with proven ROCM in biopsy or culture were evaluated. All the patients had a history of COVID-19 infection within the previous three months. The imaging findings were described and the frequency of different parameters was reported. RESULTS: Paranasal inflammation was detected in all the patients on imaging. The most common involved paranasal sinuses were ethmoid sinuses (97.9%). On diffusionweighted images, restricted diffusion was seen in the paranasal sinuses of 81.1% of the patients. In addition, sinus wall bone involvement was observed in 87.5% of the cases. The most common anatomical sites for extrasinus involvement were the retroantral soft tissue (89.6%) and orbital cavity (87.5%). Dacryocystitis in 50%, optic nerve inflammation in 43.2%, globe involvement in 18.9%, and trigeminal nerve involvement in 16% of the patients were detected. There was extension of inflammation through the cavernous sinuses and alongside the internal carotid arteries in 24% of the patients. CONCLUSION: Characteristic imaging findings of ROCM not only play a vital role in the early diagnosis of this infection, but they also contribute to the assessment of the extension of inflammation, which is vitally important in surgical planning.