RESUMO
Pyoderma gangrenosum (PG) is a very rare, non-infectious, progressive inflammatory condition falling under the umbrella of neutrophilic dermatoses. It is an ulcerative condition with a wide variety of cutaneous manifestations and multiple clinical variants (classic ulcerative, pustular, bullous, and superficial granulomatous). Additionally, owing to similar patterns of mucocutaneous ulceration, it has certain overlaps with other neutrophilic diseases frequently observed in clinical practice. Pyoderma gangrenosum may occur in association with systemic conditions such as inflammatory bowel disease, hematological malignancies, or as a part of an inherited inflammatory syndrome. However, in rare cases, it may have an idiopathic origin as well. With no specific standardized diagnostic and treatment protocols in place, the management of pyoderma gangrenosum is primarily guided by pre-existing literature or is tailored according to the individual's disease pattern, type, and associations. Currently, the pathophysiology of pyoderma gangrenosum remains elusive at best. All the aforementioned reasons contribute significantly to PG being labeled as a "diagnostic dilemma" or more commonly as a "diagnosis of exclusion" with frequent incidences of delayed diagnosis or misdiagnosis resulting in catastrophic delays in management. A 35-year-old Asian male presented with bilateral painful, violaceous ulcers with undermined edges involving the shins for the past three months. Routine investigations carried out were indicative of an underlying infection owing to a raised leucocyte count. Discharge from the lesion, however, showed no evidence of microbial growth. The ulcer progressively increased in size, despite optimal wound care and empirical treatment. Skin biopsy demonstrated central necrosis and ulceration of the epidermis and dermis with neutrophilic infiltrates. Phenomenon of pathergy was demonstrated following the formation of a new ulcer at the site of intravenous cannulation during hospital admission. Additionally, aggravation of pre-existing ulcers following their debridement was also indicative of a positive pathergy test. Ultimately, the diagnosis of pyoderma gangrenosum was made upon the successful exclusion of all the other differential diagnoses. Presence of an associated systemic disease could not be appreciated, leading to it being labeled as a case of idiopathic pyoderma gangrenosum. Supportive treatment with non-adhesive, moist dressings was initiated along with topical tacrolimus (0.1%) application. Treatment modalities utilized were steroids and azathioprine in divided doses owing to contraindications to the traditional option of cyclosporine. The patient showed a rapid response to steroids and azathioprine. The ulcers healed with characteristic cribriform scarring within three months of initiation of treatment.
RESUMO
Positron-emission tomography-magnetic resonance imaging (PET-MRI) is an emerging hybrid imaging modality that utilizes the superior soft tissue resolution of MR with the metabolic data from PET. In this study, we sought to assess the clinical value of fluorodeoxyglucose (FDG) PET-MRI with dedicated pelvic PET-MR in the initial staging of cervical cancer. In this institutional-approved study, we identified 23 adult females who underwent FDG PET-MRI on hybrid camera for staging of primary uterine cervical cancer that included a dedicated PET-MR of the pelvis. A nuclear medicine physician and a radiologist reviewed the PET, MRI, and fusion-body and pelvis images alone and then with consensus read characterizing PET and MR abnormal findings. There were 23 patients who underwent FDG PET-MRI for initial staging of cervical cancer with an average age of 52.2 ± 14.0 years. A total of 23 suspected lymph nodes in eight different patients were detected within the pelvis with increased metabolic activity on PET. Both the dedicated pelvis and whole-body PET imaging detected the same corresponding pelvic lymph nodes, although the pelvic PET imaging had better lymph node uptake delineation due to longer acquisition time. Using a 10-mm short-axis criterion, MRI identified only 43.5% of the FDG avid lymph nodes. The average SUVmax on the pelvis PET sequences was higher with SUV 8.9 ± 5.2 compared to the whole-body PET with SUV 7.8 ± 5.4 but was not statistically significant (P > 0.05). Primary cervical cancer was identified in 18 patients on both PET imaging and MRI with dedicated MR pelvis providing better characterization. Based on our results of the patients with cervical cancer evaluated for initial staging, combining dedicated pelvic PET-MRI with whole-body PET/MR provides the most complete status of malignant disease in reference to delineation of primary tumor, involvement of surrounding tissues, and regional lymph nodes.
