INTRODUCTION
Liposuction and fat grafting are commonly used techniques for achieving an ideal body shape. According to the 2022 annual statistics from the American Society of Plastic Surgeons, there were 325,669 liposuction procedures, 28,638 buttock fat grafting procedures, and 33,877 facial fat grafting procedures performed in the United States. Although the incidence of infections following these procedures is reported to be less than 1% [
1,
2], severe infections can result in full-thickness skin necrosis, underscoring the importance of meticulous postoperative management [
3].
Common pathogens causing infections include
Staphylococcus aureus, group A
Streptococcus, and
Streptococcus pyogenes. However, the severity of an infection can be significantly exacerbated by polymicrobial infections that involve anaerobes. Using antibiotics that fail to appropriately target the causative pathogens can delay treatment progress and result in more severe sequelae [
4,
5].
Prevotella bivia is an anaerobic, Gram-negative rod that predominantly inhabits the vaginal mucosa and is more commonly found in cases of bacterial vaginosis [
6]. This particular species of
Prevotella is not usually present on normal skin and is infrequently an agent of infection. However, it can become pathogenic if it enters the body during invasive procedures or in immunocompromised individuals [
7,
8]. Infections can escalate to conditions such as necrotizing fasciitis or extensive tissue necrosis, necessitating prompt diagnosis in the acute phase. Previous instances of soft tissue infections caused by
Prevotella species have been linked to invasive activities, including intravenous drug use, or associated with comorbidities such as insulin-dependent diabetes mellitus. To my knowledge, there have been no reported cases of
P. bivia infections following aesthetic procedures. In this case report, we describe two severe cases where patients developed necrotizing fasciitis and significant soft tissue defects due to
P. bivia infection.
CASE REPORT
Case 1
A 29-year-old woman presented with worsening inflammatory symptoms in the left lateral thigh area on the 17th postoperative day. She had undergone a fat harvest from the vulvar area and fat grafting to the lateral buttocks, thighs, and buttocks at a private aesthetic clinic only for women. On the 8th postoperative day, she developed swelling, erythema, and a sensation of heat at the left thigh fat graft site, accompanied by a fever spike. Despite intravenous cefazolin administration, her symptoms did not improve. Therefore, a tiny stab incision and a Penrose drain insertion were performed on the 13th postoperative day. Although her fever subsided by the 16th postoperative day, skin and soft tissue necrosis occurred and worsened (
Fig. 1A).
After the patient was referred to the hospital, computed tomography (CT) was performed on the 18th postoperative day. It revealed an extensive area of postoperative fluid collection and fat necrosis, measuring 8.6×2.6×12 cm, in the left lateral gluteal subcutaneous region (
Fig. 2). Bacterial culture identified
P. bivia as the causative pathogen. Due to the need for a long incision to facilitate drainage, and the patient’s desire to minimize or conceal the postoperative scar, incision and drainage were performed on the lateral gluteal area and the skin necrosis area of the anterolateral thigh. Two additional sessions of wound debridement and irrigation, combined with negative pressure wound therapy, were necessary. The infection caused by
P. bivia was treated with piperacillin/tazobactam.
After 2 weeks of treatment, the symptoms had improved; however, a 6×2.5 cm skin defect persisted. To address this issue, a full-thickness skin graft using tissue from the left inguinal area was performed, successfully covering the wound (
Fig. 1B).
Case 2
A 37-year-old woman visited the hospital due to severe pain and swelling in her right breast and left arm. Two weeks ago, she had undergone abdominal and arm liposuction, as well as fat grafting to the breasts and pelvic area at a private aesthetic clinic only for women. On the 9th postoperative day, she developed mastitis in the right breast, necessitating incision and fat graft removal. By the 14th postoperative day, she exhibited signs of a soft tissue infection in her left arm, characterized by swelling, tenderness, and erythema (
Fig. 3).
The CT scan revealed extensive edematous changes in the muscles of the left upper extremity, strongly suggesting a diagnosis of myositis. Additionally, subcutaneous tissue edema with gas formation was observed, raising suspicions of cellulitis (
Fig. 4). Upon initial presentation, the patient experienced severe pain throughout the left arm. Measurements showed that the circumference of both the upper arm and forearm was more than twice that of the unaffected side. Given these findings, conditions such as necrotizing fasciitis or compartment syndrome could not be ruled out. Consequently, an emergent fasciotomy of the left arm and incision and drainage of the right breast were performed (
Fig. 5A).
To minimize scarring in this young female patient, multiple small incisions were made parallel to the skin folds of the left arm. This was followed by the application of negative pressure wound therapy and the placement of drains. A turbid abscess was drained, and bacterial culture identified
P. bivia. Immediate intravenous administration of piperacillin/tazobactam was initiated. Throughout her hospitalization, she underwent three additional irrigation and debridement procedures (
Fig. 5B). By the 30th postoperative day, the patient demonstrated significant improvement in her infection symptoms and was discharged without any recurrence. However, during follow-up, hypertrophic scarring and fibrosis were observed in the right breast and left arm.
DISCUSSION
Prevotella species are pathogens commonly found in various anatomical sites, including the oral mucosa, intestinal mucosa, and urogenital tract. These bacteria are linked to a variety of infections, including periodontitis, peritonitis, intra-abdominal abscesses, and skin and soft tissue infections. Among these,
P. bivia is an anaerobic bacterium recognized as a causative agent of bacterial vaginosis [
9,
10].
In the two cases discussed, infections occurred at the sites of fat grafting, with P. bivia identified through bacterial culture. P. bivia is typically found only in the female genital area. In one of the cases, the patient who developed symptoms in the lower extremity had a history of vaginitis. The other patient had undergone a loop electrosurgical excision procedure a year prior. These details may indicate the potential for P. bivia colonization in the vaginal mucosa. In the first case, pubic fat was harvested and injected into the gluteal area, which suggests the possibility of contamination either during the liposuction process or via the cannula used for the fat injection. Additionally, both patients received treatment at a clinic specializing in liposuction and fat grafting for women, and symptoms appeared postoperatively. This situation points to the potential contamination of devices prepared before surgery.
Both cases resulted in extensive infections, including necrotizing fasciitis, which required full-thickness skin grafting in one instance and a fasciotomy in the other. To avoid such severe complications, it is crucial to conduct a comprehensive collection of the patient’s medical history, particularly any history of pelvic inflammatory disease. If the medical history is pertinent, a 7-day course of oral/topical metronidazole or a 5-day course of topical clindamycin should be prescribed. Furthermore, fat harvested from the pubic area should not be used for fat grafting. Cannulas utilized for collecting pubic fat should not be reused to harvest fat from other body areas.
Despite preventive measures, infections may still occur. If a patient’s condition fails to improve or deteriorates even after the administration of broad-spectrum antibiotics, clinicians should consider the possibility of a
P. bivia infection. In such instances, it is advisable to adjust the current antibiotic regimen or introduce additional antibiotics specifically targeting this pathogen. Since
P. bivia may be β-lactamase positive, recommended treatment options include antibiotics such as clindamycin, amoxicillin/clavulanate, metronidazole, piperacillin/tazobactam, ciprofloxacin, or imipenem [
11-
13].