Vulvar abscess

INTRODUCTION — Vulvar abscess is a common gynecologic problem that has the potential to result in severe illness [1]. These abscesses typically originate as simple infections that develop in the vulvar skin or subcutaneous tissues. Spread of infection and abscess formation in the vulvar area is facilitated by the loose areolar tissue in the subcutaneous layers and the contiguity of the vulvar fascial planes with the groin and anterior abdominal wall.

The microbiology, diagnosis, and management of vulvar abscesses are discussed here. Bartholin gland abscesses and other vulvar lesions are discussed in detail separately. (See "Bartholin gland masses" and "Vulvar lesions: Diagnostic evaluation" and "Hidradenitis suppurativa: Pathogenesis, clinical features, and diagnosis".)

ANATOMIC CONSIDERATIONS — The external female genitalia are referred to as the vulva (figure 1).

Skin and glands — Hair follicles and sweat and sebaceous glands of the vulvar skin are common sites of infection and abscess formation. The mons pubis and labia majora are covered with hair, while the labia minora are not.

Two major vulvar glands underlie the vestibule; these are the Bartholin glands (also referred to as the greater vestibular gland) and the paraurethral (Skene) glands. The Bartholin glands drain through the Bartholin ducts, located bilaterally in the vestibule at approximately the four and eight o'clock positions with respect to the vaginal introitus. The paraurethral glands empty through paraurethral (Skene) ducts, which are located bilaterally just inferior and lateral to the urethral meatus (figure 1 and figure 2) [2,3].

Fascia — The contiguity of vulvar fascial spaces with other anatomic compartments permits spread of infection from the vulva to the inner thigh, abdominal wall, or ischiorectal fossa [4,5].

The superficial fascia of the mons and labia majora, referred to as Camper fascia, contains a mesh of adipose tissue and loose, areolar connective tissue (figure 2). This layer is contiguous with the superficial fascia of the inner thighs and anterior abdominal wall.

The superficial perineal (Colle) fascia comprises the deeper layer of vulvar fascia and contains a thin, aponeurotic mesh contiguous with Scarpa fascia in the abdominal wall [6,7]. The space between Colle fascia and the inferior fascia of the urogenital diaphragm is called the superficial perineal space, and houses the vestibular bulbs and Bartholin glands [8]. Overlying these glands, but still deep to Colle fascia, is the bulbospongiosus (bulbocavernosus) muscle (figure 2).

TYPES OF VULVAR ABSCESS

Skin and hair follicle infections — The skin and hair follicles of the vulvar surface are subject to infections common to these structures in other parts of the body, and can be treated in the same manner. These include folliculitis, skin abscesses, furuncles, and carbuncles. (See "Vulvar lesions: Differential diagnosis of vesicles, bullae, erosions, and ulcers".)

Hidradenitis suppurativa also commonly affects the vulva and can be a nidus for infection that may progress to abscess. Diagnosis and treatment of hidradenitis suppurativa are discussed in detail separately. (See "Hidradenitis suppurativa: Pathogenesis, clinical features, and diagnosis" and "Hidradenitis suppurativa: Management".)

Bartholin gland abscess — Bartholin gland cysts, which form when the duct openings are obstructed, are the most common vulvar mass [4]. These cysts can evolve into abscesses, which require treatment. Bartholin gland abscesses are confined to the gland and do not spread elsewhere in the vulva. Management of Bartholin gland abscesses is discussed in detail separately. (See "Bartholin gland masses".)

Paraurethral (Skene) gland abscess — There are few reports of abscesses of the paraurethral glands [9]. (See 'Skin and glands' above.)

Wound or hematoma infections — Patients with a vulvar wound due to an obstetric laceration or vulvar surgery may develop a wound infection; this may progress to form an abscess. In addition, obstetric or other vulvar trauma may result in a hematoma, which can become infected and form an abscess. (See "Repair of perineal lacerations associated with childbirth" and "Management of hematomas incurred as a result of obstetric delivery".)

MICROBIOLOGY — Vulvar abscesses, including Bartholin gland abscesses, are often mixed polymicrobial infections, consisting primarily of methicillin-resistant Staphylococcus aureus (MRSA), enteric gram-negative aerobes, and female lower genital tract anaerobes [1,4-6,10-14]. The microbiology of vulvar abscesses is discussed in this section; Bartholin gland abscesses are discussed in detail separately. (See "Bartholin gland masses", section on 'Types of masses'.)

The vulvar skin is colonized with organisms found on the skin and in the vagina and rectum. S. aureus, streptococcal species, Escherichia coli, and other gram-negative enteric organisms are commonly isolated from vulvar abscesses [14]. Anaerobic bacteria, such as Peptostreptococcus or beta-lactamase-producing anaerobes (eg, Bacteroides fragilis) may also be present in this polymicrobial infection [6,15,16].

MRSA is the most common pathogen among vulvar abscesses that require incision and drainage [16]. There are no data regarding abscesses that do not require incision and drainage, since they are rarely cultured. The largest case series of vulvar abscesses included 162 patients at a county hospital in Texas who underwent incision and drainage [1]. MRSA was isolated in 64 percent of cases; the remaining cultures grew "usual vaginal flora," including group B streptococci, Escherichia coli, Proteus mirabilis, and Enterococcus species.

The results of this study are consistent with other United States studies showing that MRSA can be present in cultures of the vagina and rectum taken during routine obstetric care and that MRSA is the most common cause of skin and soft tissue infections at other body sites [10-12,17,18]. Athletes, military recruits, and children in day care are at increased risk for MRSA skin infections. Other risk factors include injection drug use and poor hygiene. A case series of three households suggests that heterosexual contact may be a risk for MRSA genital infections [19].

There is no evidence of Neisseria gonorrhoeae or Chlamydia trachomatis in vulvar abscesses other than Bartholin gland abscesses [20].

EPIDEMIOLOGY AND RISK FACTORS — The incidence of vulvar abscesses other than Bartholin gland abscesses is unknown.

Many patients with vulvar abscesses have no apparent risk factors. Risk factors for the development of vulvar abscesses include [1,4,16]:

●Obesity

●Poor hygiene

●Shaving or waxing of pubic hair (eg, vulvar trauma)

●Immunocompromise (eg, diabetes, acquired immunodeficiency syndrome, immunosuppressant therapy)

●Pregnancy

CLINICAL MANIFESTATIONS — Symptoms typically develop over the course of several days and persist until the abscess is treated.

Patients typically report a painful vulvar mass, sometimes described by patients as a "pimple" or a "spider bite." In addition, they may also complain of vulvar fullness or pressure, or pain with walking, sitting, or sexual intercourse [4]. Pain beyond local tenderness is not typically associated with a vulvar abscess and, particularly in immunocompromised patients, may raise suspicion for necrotizing fasciitis. (See "Necrotizing soft tissue infections", section on 'Clinical manifestations'.)

There are few data regarding how often vulvar abscess is accompanied by fever. In one study, fewer than 10 percent of patients with vulvar abscesses had an associated temperature ≥100.4°F [1].

DIAGNOSIS AND EVALUATION — The diagnosis of vulvar abscess is based on the finding on physical examination of a tender, often fluctuant vulvar mass with surrounding erythema and possible edema and/or induration (picture 1) [5].

Evaluation

Physical examination — Vital signs are measured to assess for fever and hemodynamic stability, particularly in patients who report fever, are ill-appearing, or are immunocompromised.

The site of the suspected vulvar abscess is examined. The vulva should be visually inspected and the mass palpated. Signs consistent with an abscess (tender mass, fluctuance, erythema, edema, induration) should be noted. The size of the abscess should be measured and documented; this information is useful to assess response to therapy. The extent of the mass should be assessed by visualization of any vaginal component with a speculum examination and with palpation of the mass with a bimanual pelvic examination. Any mass that does not have findings typical for an abscess should be evaluated further, as appropriate. (See 'Differential diagnosis' below.)

Laboratory evaluation — Given the increasing prevalence of resistant organisms, such as methicillin-resistant S. aureus, aerobic and anaerobic cultures should routinely be collected. Since vulvar abscesses other than Bartholin gland abscesses are not caused by gonorrhea or chlamydia, testing for these infections is not part of the evaluation [14]. In abscesses that require incision and drainage, cultures are collected after the initial incision. Cultures are collected by needle aspiration at the leading edge of cellulitis if no incision is planned.

Laboratory evaluation to evaluate for bacteremia and sepsis is required in the few patients who develop systemic illness. (See "Detection of bacteremia: Blood cultures and other diagnostic tests".)

Other tests — Radiographic data do not generally contribute to the diagnosis since the extent of the abscess is typically palpable on examination. The extent of deeper abscesses is evaluated during incision and drainage. If spread of infection beyond the vulva is suspected, imaging with ultrasound or computed tomography may be utilized [21]. In the pediatric population, some experts use translabial ultrasound to differentiate cellulitis from a drainable abscess. This may be helpful in avoiding an unnecessary operative procedure.

Biopsy of the lesion is appropriate for patients in whom malignancy is suspected. It is generally recommended that patients over age 40 with a Bartholin cyst or abscess undergo drainage and biopsy of the gland to exclude the possibility of an underlying carcinoma. (See "Bartholin gland masses", section on 'Types of masses'.)

Differential diagnosis — The differential diagnosis of a vulvar abscess includes infectious and noninfectious vulvar masses and lesions. Abscesses are generally singular and present as a palpable mass rather than an ulcer or flat lesion (macule, patch, plaque) and may begin small, but are larger than a papule. (See "Vulvar lesions: Differential diagnosis of vesicles, bullae, erosions, and ulcers".)

Other infections of the vulva include vulvovaginitis, which does not present with a mass or rarely presents with erythema. Genital herpes simplex infection causes painful papules, but these are too small to be abscesses. Necrotizing fasciitis, although rare, should be suspected in a woman who has a vulvar abscess and/or persistent vulvar pain combined with erythema or induration. (See 'Necrotizing fasciitis' below.)

Noninfectious masses are typically nontender and nonerythematous (eg, Bartholin gland cyst, epidermoid cyst). Notable exceptions to this are vulvar nodules due to hidradenitis suppurativa, which are painful and often progress to form an abscess. Vulvar cancer may present as a firm mass or lesion with surrounding erythema. A biopsy should be performed if there is suspicion of a cancer or precancerous lesion.

MANAGEMENT

General approach — Treatment of vulvar abscess depends upon the lesion size and the patient's risk factors for failure of therapy or systemic infection. The general principles of management are the same regardless of the type of vulvar abscess.

Small lesions often resolve with conservative therapy (eg, warm compresses); however, incision and drainage is the mainstay of treatment of vulvar abscesses [1,22]. Antibiotics are required in some cases [1]. (See 'Complications' below.)

Indications for referral — Lesions that are appropriate for conservative therapy (eg, warm compresses) may be treated by any primary care clinician (see 'Conservative therapy' below). Incision and drainage requires a clinician who has experience with vulvar procedures.

Consultation with an advanced pelvic surgeon may be required if the abscess extends into the mons pubis and/or into the medial aspect of the thigh or if necrotizing fasciitis is suspected.

Small abscesses — The first line of therapy for most patients with a small vulvar abscess (<2 cm) is conservative therapy (eg, warm compresses or sitz baths). Antibiotic therapy may be used in combination with conservative measures.

Conservative therapy — Small vulvar abscesses (<2 cm) that have yet to point to the skin surface ("come to a head") are treated with warm compresses or sitz baths three to four times per day. If the lesion does not resolve after a week or if the lesion points to the skin's surface, incision and drainage will hasten resolution [14].

For immunocompromised patients, conservative management should be used only for abscesses that are too small for incision and drainage.

Antibiotics combined with conservative therapy — Initial treatment of a small vulvar abscess with conservative therapy alone is reasonable. Antibiotic therapy should be initiated if the lesion does not improve after two days of conservative therapy or if the patient is immunosuppressed. (See 'Immunocompromised patients' below.)

Choice of antimicrobial agent is the same as for patients who have undergone incision and drainage and is discussed in detail below. (See 'Antimicrobial agents' below.)

Incision and drainage — For patients with small abscesses (<2 cm), we perform incision and drainage if the patient is immunosuppressed, if the lesion is still present after one week, or if it points to the skin surface. (See 'Incision and drainage' below.)

Larger abscesses — For patients with a vulvar abscess ≥2 cm, we suggest incision and drainage. For patients with vulvar abscess >5 cm, inpatient management may be required [14,21].

Incision and drainage — The procedure for incision and drainage described here varies slightly from that for a Bartholin gland abscess (the abscess cavity is packed rather than placement of a Word catheter). The procedure for Bartholin abscesses is described in detail separately. (See "Bartholin gland cyst and abscess: Word catheter placement".)

Operative setting — Incision and drainage of a vulvar abscess is typically managed in the outpatient setting [4]. Occasionally, a vulvar abscess will require extensive debridement in an inpatient setting. When extensive debridement is anticipated, an experienced pelvic surgeon should perform the procedure.

Inpatient incision and drainage under regional or general anesthesia is preferred if an abscess is very large (≥5 cm), if there is suspicion that the abscess may extend to another anatomic compartment (eg, thigh, anterior abdominal wall), or in immunocompromised patients. If there is a potential for postdrainage complications, we also admit the patient for postoperative observation.

Procedure — Aspects of incision and drainage specific to vulvar abscess are discussed here. General principles of incision and drainage of a skin abscess can be found separately. (See "Techniques for skin abscess drainage".)

Incision and drainage of a vulvar abscess is performed in the dorsal lithotomy position. Local anesthetic is injected at the planned incision site and around the base of the abscess. A pudendal block is not recommended, since it does not anesthetize the anterior aspect of the perineum and is often ineffective. (See "Pudendal and paracervical block".)

For drainage of abscesses that are ≥5 cm, the procedure may need to be performed under general anesthesia to ensure patient comfort and achieve adequate exposure.

An incision in the anterior-posterior axis of the vulva is preferred (picture 2). This optimizes exposure, since the anterior-posterior axis of the vulva is larger than the medial-lateral axis. In addition, during the healing process, there will be less tension on the incision, due to the normal forces during movement in the vulvar area.

The incision should extend the length of the indurated vulvar tissue. A generous incision is required to allow complete drainage and irrigation of the abscess. A small incision may be inadequate and result in a wound that is more difficult to pack postoperatively.

Abscess fluid and debrided material should be sent for aerobic and anaerobic culture and susceptibility testing. The base of the abscess should be debrided until all necrotic tissue has been removed. Consultation with an advanced pelvic surgeon may be required if the abscess extends into the mons pubis and/or into the medial aspect of the thigh or if necrotizing fasciitis is suspected.

As with incision and drainage at other body sites, the defect should be drained, irrigated, and packed with gauze (picture 2). This saline-soaked gauze is removed and replaced daily ("wet to dry").

There are several options for wound management after an incision and drainage of a vulvar abscess. One option is wet to dry dressing changes, having the wound heal by secondary intention, from the base upward until the defect has healed and closed. The cavity becomes smaller and smaller with time, requiring less packing material. The patient and/or family must be comfortable with changing the wet to dry dressings, or home health care must be arranged. Another option is to place sutures in the operating room, but not tie them. Initially, wet to dry dressing changes are done for approximately three to seven days. Then the sutures are tied together, to approximate the edges of the cavity for healing [21].

Wound management should be individualized based on the size and depth of the incision and drainage cavity, to prevent re-infection and assure proper healing. We have even used wound vacuums in some patients. These work well, and potentially offer more rapid wound healing, although they are often more costly than some other options. (See "Negative pressure wound therapy".)

Antibiotic therapy after drainage — The role of antibiotic therapy following incision and drainage of vulvar abscesses is uncertain. No high quality data address this question. The microbiology of skin abscesses at other body sites differs from vulvar abscesses, so it is not known whether data from other sites can be extrapolated to treatment of vulvar lesions.

The most relevant study regarding this question was a randomized trial of patients with uncomplicated skin abscesses (including groin and buttock abscesses) treated in an emergency department in which incision and drainage was performed in combination with seven days of trimethoprim-sulfamethoxazole (oral, 160 mg/800 mg twice daily) or placebo [23]. The rate of treatment failure was comparable for both groups (17 versus 26 percent), but patients treated with antibiotics had a significantly lower rate of recurrent abscesses within 30 days of enrollment (9 versus 28 percent).

●In the absence of direct data from well-designed studies, we suggest an initial approach of incision and drainage combined with antibiotic therapy for patients with the following risk factors for failure of therapy or dissemination of infection, including [21,24]:

•Size ≥5 cm.

•Location makes abscess difficult to drain completely.

•Infection extends into other anatomic compartments (eg, abdominal wall or thigh).

•Extensive or rapidly progressing surrounding cellulitis.

•High likelihood of being methicillin-resistant S. aureus (MRSA)-positive (table 1).

•Systemic signs of infection.

•Immunocompromised patient.

•Recurrent symptomatic abscess.

Disseminated infection is rare, but avoiding the severity of potential sequelae of disseminated infection outweighs the risks of adverse reactions from antibiotics or promoting antibiotic resistance. (See 'Complications' below.)

Delayed addition of antibiotic therapy is required for patients with abscesses that do not resolve following incision and drainage (see 'Antibiotics combined with conservative therapy' above). Some patients may require further debridement. Since this judgment will be made days to weeks after the drainage procedure, antimicrobial agents should be selected according to the results of the abscess culture. (See 'Follow-up' below.)

Since culture results require several days to process, it is likely that some patients who were not treated with antibiotics will be found to have a MRSA-positive abscess. In these patients, antibiotics need to be initiated only if the abscess is not resolving. (See "Methicillin-resistant Staphylococcus aureus (MRSA) in adults: Treatment of skin and soft tissue infections", section on 'Oral antibiotic therapy'.)

Antimicrobial agents — Antibiotic therapy for patients with a vulvar abscess should provide adequate coverage for MRSA and enteric gram-negative aerobes; for severe infections, antibiotic therapy should also include coverage for anaerobes. Empiric therapy selection should be tailored to culture and susceptibility results when available [1,16,21].

Oral antibiotic regimens for vulvar abscess are shown in the table (table 2).

Intravenous therapy is warranted if any one of the following features are present: signs of systemic illness (fever >100.4°F [38°C] and chills with sustained tachycardia), rapid progression of erythema, proximity to an indwelling medical device such as a vascular graft, necrotizing fasciitis, or inability to tolerate oral medications (see 'Complications' below). Management of these patients may require consultation with a specialist in infectious diseases. Intravenous antibiotic regimens for vulvar abscess are shown in the table (table 2).

Further details regarding treatment of MRSA skin and soft tissue infections are found elsewhere. (See "Methicillin-resistant Staphylococcus aureus (MRSA) in adults: Treatment of skin and soft tissue infections".)

Duration of therapy — Duration of antibiotic therapy for treatment of vulvar abscess depends on the severity of infection and the clinical response to therapy.

Patients with severe infection who require parenteral therapy are usually treated for a total duration of 7 to 10 days. Some experts advocate for a total of 14 days of antibiotic therapy [21]. Intravenous therapy can be switched to an oral regimen, preferably tailored to the culture and susceptibility results, after signs of infection begin to resolve.

Immunocompromised patients — Immunocompromised patients with a vulvar abscess should be treated with incision and drainage (see 'Incision and drainage' above), except in the few cases in which the abscess is too small to drain.

In immunocompromised patients, it is preferable to perform incision and drainage in an inpatient setting under regional or general anesthesia. This permits adequate exploration of the extent of the abscess. Postoperative inpatient care is prudent to observe for persistent infection. We admit all patients with diabetes for inpatient care, since in these patients, the default diagnosis is necrotizing fasciitis until proven otherwise.

FOLLOW-UP — We see patients who were treated as outpatients for vulvar abscess at two days and then two weeks after initiation of treatment.

We examine the signs of ongoing infection. An abscess that is resolving will decrease in size and other physical examination findings (tenderness, erythema, fluctuance, and induration) will improve and then disappear. These changes generally become evident approximately 48 hours after treatment is initiated.

After an abscess resolves, a firm area at the abscess site may remain. This is likely scar tissue due to the inflammatory process associated with the abscess. If the mass shows no signs of ongoing infection on examination, the patient can be reassured that no further treatment is necessary.

Patients should be counseled to call if they have fever or there is an increase in the size of the mass or surrounding erythema.

Follow-up after inpatient treatment should be individualized according to the severity of illness, patient comorbidities, and the extent of surgical debridement.

COMPLICATIONS

Recurrent abscess — Vulvar abscesses may recur immediately after or remote from treatment. In the series of 162 patients described in a preceding section, the rate of recurrence after incision and drainage with selected use of antibiotics was 6 percent [1] (see 'Microbiology' above). In addition, 27 percent of patients had a history of a previous vulvar abscess; it is unknown whether these occurred at the same site.

Sepsis — Vulvar abscesses may rarely be complicated by sepsis, as with any type of abscess, particularly in patients who are immunocompromised [4,25,26]. In the series of 162 patients with vulvar abscess described in a preceding section, two patients required admission to an intensive care unit [1] (see 'Microbiology' above). One of these patients, a woman with diabetes, died.

Sepsis should be suspected in patients who are febrile and exhibit hemodynamic instability. The diagnosis and management of sepsis are discussed in detail separately. (See "Evaluation and management of suspected sepsis and septic shock in adults".)

Necrotizing fasciitis — Necrotizing fasciitis is a rare, but potentially devastating, sequela of vulvar skin and soft tissue infection (picture 3) [5,27,28]. Necrotizing fasciitis should be considered in patients with diabetes as well as those with fever, soft tissue involvement with pain out of proportion to skin findings, and hemodynamic instability. Surgical exploration and biopsy are the only ways to definitively make the diagnosis.

Vulvar necrotizing fasciitis may present as progressive edema and erythema surrounding a surgical incision or a simple vulvar infection. The hallmark of vulvar necrotizing fasciitis is a woody induration extending onto the inner thighs; crepitus may or may not be present [14]. Pelvic imaging may be useful. In some cases, imaging studies identify gas bubbles in tissue planes indicating an infection with gas producing organisms. (See "Necrotizing soft tissue infections", section on 'Radiographic imaging'.)

Vulvar necrotizing fasciitis is an emergency. Treatment should be immediate, extensive debridement of the necrotic tissue until normal, bleeding tissue is encountered (picture 4). Margins of normal tissue should be removed around the necrotic areas to prevent spread of microscopic disease. The surgical site should be packed, and seriously ill patients should be transferred to the intensive care unit for supportive care. (See "Basic principles of wound management", section on 'Wound debridement'.)

Diagnosis and treatment of necrotizing fasciitis are discussed in detail separately. (See "Necrotizing soft tissue infections".)

PREVENTION OF RECURRENCE — Patients who have had a previous methicillin-resistant S. aureus (MRSA) infection may be at risk for recurrent skin and soft tissue infection. (See "Methicillin-resistant Staphylococcus aureus (MRSA) in adults: Epidemiology".)

Measures to prevent MRSA infection are discussed in detail separately. (See "Methicillin-resistant Staphylococcus aureus (MRSA) in adults: Prevention and control".)

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Gynecologic infectious diseases (non-sexually transmitted)".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Bartholin gland cyst (The Basics)")

SUMMARY AND RECOMMENDATIONS

●Anatomic considerations

•Vulvar abscesses most commonly originate as simple infections that develop in the vulvar skin or subcutaneous tissues superficial to the fascia. (See 'Introduction' above.)

•Spread of infection and abscess formation in the vulvar area is facilitated by the loose areolar tissue in the subcutaneous layers and the contiguity of the vulvar fascial plans with the groin and anterior abdominal wall. (See 'Anatomic considerations' above.)

●Microbiology – The vulvar skin is colonized with organisms commonly found on the skin and in the vagina and rectum; many vulvar abscesses are mixed polymicrobial infections. Methicillin-resistant Staphylococcus aureus (MRSA) is the most common organism. (See 'Microbiology' above.)

●Diagnosis – The diagnosis of vulvar abscess is based on finding a fluctuant, tender vulvar mass with surrounding erythema and possible edema and/or induration on physical examination (picture 1). Radiographic or laboratory data do not significantly contribute to the diagnosis. (See 'Diagnosis and evaluation' above.)

●Management

•For immunocompetent patients with small infections (<2 cm), we suggest conservative therapy (eg, warm compresses or sitz baths) (Grade 2C). We also treat these patients with antibiotic therapy (table 2). Another reasonable approach is to initiate antibiotics in these patients only if the lesion does not improve after two days. For immunocompromised patients, conservative management should be used only for abscesses that are too small to drain. (See 'Conservative therapy' above.)

•For a vulvar abscess ≥2 cm in an immunocompetent patient and for any drainable vulvar abscess in an immunocompromised patient, we suggest incision and drainage (Grade 2C). Abscess fluid and debrided material should be sent for culture and susceptibility testing. (See 'Incision and drainage' above.)

•For patients with vulvar abscesses who have risk factors for failure of therapy or dissemination of infection (systemic signs of infection, immunocompromise, suspected MRSA-positive abscess (table 1), extensive surrounding cellulitis, abscesses that are >5 cm or track into other anatomic compartments, or recurrent abscess), we suggest antibiotic therapy in addition to incision and drainage (Grade 2C) (table 2). (See 'Antimicrobial agents' above.)

•Abscesses that do not resolve or worsen following drainage also require antibiotic treatment (table 2) and, in some cases, further debridement. (See 'Antibiotic therapy after drainage' above.)

●Complications – Potential complications of vulvar abscess are recurrent abscess, sepsis, and necrotizing fasciitis. (See 'Complications' above.)