Hospitalization rate and patterns of clinical reasons among Mpox-confirmed cases: a systematic review and meta-analysis

Mpox, caused by the monkeypox virus, has recently re-emerged as a global public health concern. The hospitalization rates and the reasons for mpox-confirmed patients remain inconsistently reported, with prior studies using different case definitions and reasons for admission. In light of these inconsistencies and the resurgence of the mpox threat, this systematic review and meta-analysis aimed to provide an updated assessment of the hospitalization rate and clinical reasons among mpox-confirmed patients. Online database searches, including PubMed, Hinari, CINHAL, EMBASE, Google, and Google Scholar, as well as manual searches from national and international reporting websites, were conducted. Studies were included if they reported on laboratory-confirmed mpox cases with or without hospitalization reasons. Data extraction followed a standardized protocol, and the quality of the included studies was assessed using the Joanna Briggs Institute critical appraisal tool. A meta-analysis was performed to pool the effect sizes. A random effect model was used to estimate the pooled effect sizes. Heterogeneity among the included studies was assessed using Cochran’s Q test and I2 statistics. Subgroup analysis, sensitivity analysis, and meta-regression were carried out to identify the source of heterogeneity. A funnel plot and Egger’s test were used to assess publication bias. Among the 441 studies identified, 45 that fulfilled the eligibility criteria were included for the final analysis, consisting of 25,367 mpox confirmed study participants and 1606 hospitalized cases. The pooled hospitalization rate across the included studies was 8.0% (95% CI: 6.0, 11.0) with significant heterogeneity. Subgroup analysis by region revealed that the highest pooled rate of hospitalization was observed in Africa, and the lowest was in Europe. A significant publication bias was detected, and a trim-and-fill analysis identified nine missing studies. After adjusting for these, the pooled hospitalization rate for mpox increased slightly to 10.5% (95% CI: 8.3, 12.8). Of the total included studies, 34 studies involving 792 confirmed mpox patients reported clinical reasons for hospitalization, and 15 clinical reasons were analyzed. The most common reasons were unspecified severe pain (46.0%), followed by non-anogenital cellulitis/cutaneous bacterial superinfection (38.8%) and genital edema with or without phimosis/paraphimosis (34.9%). Significant heterogeneity was also observed across several hospitalization reasons. Hospitalization among mpox-confirmed patients was relatively low, and the most common clinical reasons for admission were unspecified severe pain, followed by bacterial infections of the skin. The study highlights the need for improved pain management, infection control, and early intervention to reduce hospital admissions. It also calls for standardized hospitalization criteria and reporting to improve comparisons across studies that aid clinicians and public health authorities in the management of mpox outbreaks.