Introduction: In 2022, an outbreak of human monkeypox (MPX) spread globally infecting over 75,000 people. We describe the clinical course and management of a large cohort of men with intermediate follow-up infected with MPX with penile lesions. We also describe a putative grading system that can help treating physicians in managing these patients. Methods: We conducted a retrospective analysis of adults initiated on tecovirimat for treatment of MPX infection with genital involvement at Columbia University Irving Medical Center between June and August 2022. We reviewed clinical information including images of the genital lesions at initial and follow up visits. A novel Monkeypox Penile Lesion Grading (MPLG) system was developed for lesions. Images were then re-reviewed and grades were assigned based off the MPLG criteria. Results: 68 (59.6%) of 114 subjects had penile lesions in the final analysis. Mean age was 34.7 years old and all were men. 100% of these men reported having recent sexual contact with other men. The mean follow up period was 20.3 days. There were 31 (46%), 14 (20%), 12 (18%), and 11 (16%) subjects rated MPLG-1 to MPLG-4 (Table 1). The majority (76%) of these penile lesions resolved over the follow up period without any complication. However, there were a few patients that did have poorly healing lesions that led to penile scarring, contraction or discoloration at the end of their follow up period, labeled as penile complications. Rates of penile complications increased with increased severity of the lesions with rates of 4%, 25%, 36%, and 72% for MPLG1-4 lesions, respectively (Figure 1). Conclusions: We report the largest known series of MPX penile lesions undergoing treatment with tecovirimat and a novel MPLG grading system to stratify these lesions. There was a strong correlation with novel MPLG classification and penile complication rates. Reassuringly, none of the cases required surgical intervention and the majority of the lesions healed with conservative management. SOURCE OF Funding: None
