The search obtained 78 records, two of which were identical. After scrutinizing the titles and abstracts, 67 articles were eliminated, and 14 studies were incorporated into the systematic review following an in-depth examination of the full texts. The PRISMA flow diagram (Fig. 1) illustrates the selection process and the reasons for exclusion.

All of the selected case reports were evaluated using the JBI checklist for case reports (Table 1). Although there is no definition of how to define the low risk of bias from the JBI checklist manual, the risk of bias in all case reports included in the review can be considered low since all criteria from the JBI checklist were fulfilled in each case report [12].

This systematic review included 14 case reports (Table 1) [14,15,16,17,18,19,20,21,22,23,24,25,26,27]. The case reports were published between 2016 and 2022. Five cases were reported in America [14, 15, 18,19,20] and 4 cases in Europe [21, 22, 25, 27], 3 cases in Asia [17, 23, 24], and 2 cases in Australia [16, 26].

Clinical characteristics are presented in Table 2 in Appendix. The age of patients ranged from 34 to 72 years, with a median of 57 years. We found 10 articles describing cases in men; 8 studies reported patients with obesity, with a BMI exceeding 30 kg/m2; 5 studies reported hypertension; 3 patients were smokers and 1 was a former smoker. Common symptoms include pain, swelling, and redness in the genital area and groin. [14,15,16, 24]. One study reported painless discomfort for several days. After physical examination, a broad perineal abscess with 5 cm of necrotic tissue is a significant finding. [20]. In 4 cases, the patient may come with a toxic appearance accompanied by a fever. It is important to emphasize that our systematic review included 4 cases with systemic symptoms [14, 22, 25, 27]. Among these symptoms, pain and swelling of the scrotum are the most common complaints. HbA1C level was between 6.50% and 13.20%

All cases confirmed the presence of FG and had a history of use of SGLT2i. The duration of SGLT2i therapy varies widely, ranging from 6 months to 6 years. Only 2 studies did not mention the duration of drug consumption [14, 15]. Currently, 3 different drugs in the SGLT2i class have been approved for sale on the market, namely Dapagliflozin, Empagliflozin, and Canagliflozin. The use of Dapagliflozin was reported in 7 cases [15, 17, 20, 22, 25,26,27], Empagliflozin in 5 cases [15, 16, 18, 23, 24] and Canagliflozin in 2 cases [19, 21]. Three cases used only SGLT2i, and the rest were in combination with other antidiabetic drugs.

Complications associated with FG indicate sepsis observed in 2 cases. Other cases are peripheral neuropathy, Hashimoto's hypothyroidism, horseshoe abscess and posterior communication of bilateral ischiorectal fossa, diabetic ketoacidosis, delirium, and derailed diabetes mellitus.

Regarding disease management, all studies (14 studies) have discontinued certain SGLT2i and replaced them with other therapies. Two studies reported the resumption of therapy [24, 25], and 2 studies reported permanent discontinuation of SGLT2i therapy [22, 27]. The other 10 cases in their report only indicated drug discontinuation and did not report permanent or reintroduction of the drug. The therapies include aggressive debridement, antibiotics, fluid resuscitation, incisions, drainage, or insulin, rigid sigmoidoscopy, perianal ring block, surgery, hyperbaric oxygen therapy, plastic surgery, and faciocular flap. It should be noted that not all studies included in this review had complications [14, 18,19,20,21] (Table 3 in Appendix).

The results of the therapy showed improvement. Seven cases reported patients discharged in the range of 9–51 days after receiving antibiotics and glucose control [15,16,17, 20,21,22,23,24, 26]. Three other cases reported progress in patient stability and wound healing [14]. A total of 4 cases did not report the results of the follow-up cases [18, 19, 25, 27].