Bromhidrosis

INTRODUCTION — Sweat-related body odor manifests in essentially all individuals at some point during life. Excessively foul-smelling sweat is considered pathologic and termed "bromhidrosis," a term derived from the Greek "bromos" (stench) and "hidros" (sweat). Synonyms of bromhidrosis include "bromidrosis," "osmidrosis," and "ozochrotia."

The degree of odor considered "excessive" and sufficient for a diagnosis of bromhidrosis is not definitive. Bromhidrosis is generally diagnosed when noticeable body odor has a negative effect on an individual's self-esteem, social interactions, or quality of life.

Bromhidrosis is divided into apocrine bromhidrosis and eccrine bromhidrosis. The most common site for apocrine bromhidrosis is the axilla. Eccrine bromhidrosis most often affects the feet.

The clinical features, diagnosis (algorithm 1), and management of bromhidrosis will be reviewed here. Hyperhidrosis (excessive sweating) is reviewed separately. (See "Primary focal hyperhidrosis".)

CLASSIFICATION

Apocrine versus eccrine bromhidrosis — Bromhidrosis is subdivided into apocrine and eccrine variants based upon the type of sweat gland involved.

●Apocrine glands – Apocrine glands develop after puberty and are most densely distributed in the axillae, anogenital areas, and areolae. The primary role of apocrine glands appears to be the secretion of pheromones.

●Eccrine glands – Eccrine glands are widely distributed all over the body, with the exception of the external auditory canal, lips, clitoris, labia minora, and glans penis. Eccrine glands are primarily responsible for thermoregulation and are found over most of the skin surface.

Apoeccrine glands are an additional type of sweat gland that are smaller than apocrine glands and exhibit features of both apocrine and eccrine glands. Apoeccrine glands localize to the axillae and genital skin and likely also contribute to bromhidrosis.

Localized versus generalized — Bromhidrosis is subdivided into localized and generalized presentations.

●Localized bromhidrosis – Localized bromhidrosis is limited to specific body areas and may occur with either apocrine or eccrine bromhidrosis. Common sites for localized bromhidrosis are the axillae (apocrine bromhidrosis) and the feet (eccrine bromhidrosis).

●Generalized bromhidrosis – Generalized bromhidrosis refers to bromhidrosis not localized to specific body areas. Generalized bromhidrosis is a form of eccrine bromhidrosis.

EPIDEMIOLOGY — The incidence of bromhidrosis is unknown. Pathologic body odor appears to be a more common concern in societies where body odor is considered particularly offensive. Males are more often affected than females.

Apocrine bromhidrosis occurs after puberty, and it appears to be rare in older adults. Eccrine bromhidrosis can occur at any age.

PATHOGENESIS — All sweat glands are controlled by the sympathetic nervous system. Primary stimuli include heat, exercise, and emotion; other stimuli include certain foods, medications, and disease states.

Mechanism of malodor — Sweat is usually odorless when secreted from the sweat gland. Bacterial degradation of secreted sweat or keratin is the primary mechanism leading to bromhidrosis. Occasionally, other factors are responsible for malodor.

Apocrine bromhidrosis — Bacteria, pheromones, and patient-specific factors (eg, sweat gland biology, hygiene practices) may contribute to apocrine bromhidrosis. Because of the limited number of body locations with numerous apocrine glands (axillae, anogenital areas, breast), apocrine bromhidrosis is always localized.

Mechanism — Degradation of apocrine secretions by bacteria is the major cause of apocrine bromhidrosis. Examples of odiferous fatty acids found in axillary secretions include E-3-methyl-2-hexenoic acid (E-3M2H), 3-hydroxy-3-methyl-hexanoic acid, sulfanylalkanols, and 3-methyl-3-sulfanylhexan-1-ol. In the case of E-3M2H, apocrine secretion odor-binding proteins (ASOB1 and ASOB2) bind E-3M2H before it reaches the skin surface [1]. After reaching the skin surface, E-3M2H is released by enzymes in bacterial flora, resulting in malodor.

A variety of bacteria can degrade apocrine sweat. Corynebacterium species are frequent colonizers in the axillae and contain a zinc-dependent N-alpha-acyl-glutamine aminoacylase implicated in axillary odor [2]. Other bacteria, including Staphylococcus, Cutibacterium (formerly Propionibacterium), and Acinetobacter species, can break down fatty acids into thioalcohols and other odiferous compounds [3]. Treatment of Sphingomonas paucimobilis colonization in the axilla has led to resolution of odor in a patient with bromhidrosis [4].

Secretion of pheromones from apocrine glands also contributes to axillary odor. The pheromones androstenone (5alpha-androst-16-en-3-one) and androstenol (5alpha-androst-16-en-3alpha-ol) are malodorous even before bacterial degradation [5].

Other contributory factors — Certain characteristics may influence the risk of bromhidrosis. Findings among patients with bromhidrosis have included larger and more numerous apocrine glands compared with patients without bromhidrosis [6] and higher levels of dihydrotestosterone than testosterone in the nuclear fraction of axillary skin compared with uninvolved skin, suggesting a role for 5-alpha-reductase [7,8]. Higher sweat volume (ie, hyperhidrosis) may also be associated with odor [9]. In addition, familial bromhidrosis with an apparent autosomal dominant inheritance pattern has occurred [10].

Poor hygiene that promotes bacterial overgrowth may be associated with bromhidrosis, particularly in patients with diabetes, obesity, or concomitant intertriginous skin diseases, such as intertrigo, erythrasma, and trichomycosis axillaris. Bromhidrosis has also occurred after laser depilation of the axilla [11]. (See "Intertrigo" and "Erythrasma" and "Trichomycosis (trichobacteriosis)".)

Eccrine bromhidrosis — Sweat and skin maceration are key factors in the development of localized eccrine bromhidrosis.

Mechanism — Localized eccrine bromhidrosis occurs as a result of sweating leading to skin maceration, which results in bacterial overgrowth and degradation of keratin. Generalized eccrine bromhidrosis results from the excretion of malodorous sweat and is associated with systemic disease or exposure to certain foods, medications, or toxins.

Other contributory factors — Localized eccrine bromhidrosis typically occurs in association with factors that contribute to skin moisture, such as hyperhidrosis. Skin folds (eg, skin under a pannus) or other occluded skin sites may hold moisture and microorganisms that generate fetor. Patients may also have concomitant cutaneous disorders that also occur in the setting of chronic skin moisture and may contribute to malodor, such as intertrigo, erythrasma, and pitted keratolysis (picture 1). (See "Intertrigo" and "Erythrasma" and "Pitted keratolysis".)

Generalized eccrine bromhidrosis can occur in association with a wide variety of systemic disorders. Generalized eccrine bromhidrosis usually occurs as a result of ingestion of odor-promoting compounds or systemic illness. Examples of associated factors include:

●Diet (eg, garlic, onion, curry, alcohol ingestion)

●Medications (eg, penicillin, bromides)

●Inborn errors of metabolism (eg, phenylketonuria, trimethylaminuria, isovaleric acidemia, hypermethioninemia)

●Systemic disease (eg, liver or renal failure, gout, scurvy, typhoid, hidradenitis suppurativa)

There are rare reports of generalized bromhidrosis following whole-body laser hair removal or in association with an intranasal foreign body in a child [12,13].

CLINICAL PRESENTATION — The key clinical manifestation of bromhidrosis is localized or generalized malodor. Patients may also exhibit physical findings of associated disorders.

●Odor – The odor of bromhidrosis may be described as "rancid," "pungent," or "sour." It may be exacerbated by heat or exercise and briefly alleviated by bathing.

●Location – Apocrine bromhidrosis is always localized, with involvement limited to areas of numerous apocrine glands (eg, axilla, anogenital area, breasts). Axillary involvement is most common.

Eccrine bromhidrosis may be localized or generalized. Localized eccrine bromhidrosis often involves the feet.

●Physical findings – Skin in the affected area may appear normal. In sites with associated hyperhidrosis, skin may appear macerated with moist, overlying scale. There may also be physical findings of other cutaneous disorders associated with chronic skin moisture.

DIAGNOSIS — The diagnosis of bromhidrosis is made based on the patient history and physical examination.

In general, skin biopsies are not indicated or helpful for the diagnosis of bromhidrosis. Apocrine and eccrine glands and ducts do not show specific abnormalities in bromhidrosis. There may be a relative increase in the size and number of sweat glands [6].

Assessment of odor — Clinicians are usually able to diagnose bromhidrosis through smelling the affected area and obtaining a history of offensive odor noted by the patient and others. Exacerbation of odor in scenarios where sweating is stimulated, such as hot environments or during exercise, is characteristic.

Odor may be subtle at the time of examination if the patient has recently bathed. If it is not obvious, the patient should be asked if the odor has been noticed by others to aid in identifying patients who may not have bromhidrosis. Activity to induce sweating (exercise, exposure to heat) may also be helpful in making the diagnosis when odor is not immediately apparent. (See 'Differential diagnosis' below.)

Assessment for contributory factors — After the presence of bromhidrosis is confirmed, patients should be assessed for potential contributory factors.

Localized bromhidrosis — We typically inquire about a history of excessive sweating if excessive sweating was not evident during the examination of the affected area. The site of bromhidrosis should be physically examined to assess dermatologic conditions that may contribute to malodor (eg, intertrigo in skin folds, pitted keratolysis on feet). Our assessment also typically involves a discussion of hygiene practices to identify patients who may benefit from adjustments to their hygiene routine.

Generalized bromhidrosis — For patients with generalized bromhidrosis, a history and physical examination can be helpful for eliciting underlying causes. The clinician should inquire about diet, current medications and supplements, inborn errors of metabolism, and systemic diseases. A review of systems and physical examination should be performed to detect signs and symptoms of internal disease. A social history regarding hobbies and occupation may also help identify external causes of malodor. For children with generalized bromhidrosis, we also ask about the possibility of an intranasal foreign body [13]. (See 'Eccrine bromhidrosis' above.)

The type of odor noted can aid in narrowing the list of potential causes of generalized bromhidrosis. The odor of food-related bromhidrosis often resembles the type of food ingested (eg, garlic, onion, curry). Malodor related to liver or renal failure may yield an ammonia-like smell. Odors associated with specific metabolic disorders are reviewed separately. (See "Inborn errors of metabolism: Epidemiology, pathogenesis, and clinical features", section on 'Abnormal odors'.)

Additional evaluation is directed based upon the patient history and physical examination. When the cause of generalized bromhidrosis is not obvious, we obtain the following laboratory tests to assess for liver or renal disease:

●Liver function tests

●Renal function tests

The need for additional testing for toxin exposure and other disorders is based upon the findings of the history and physical examination. (See 'Eccrine bromhidrosis' above.)

DIFFERENTIAL DIAGNOSIS — Bromhidrosis should be distinguished from neurologic or psychiatric conditions that cause the patient to believe offensive body odor is present though odor is not apparent to others. A lack of noticeable odor on examination, an absent history of odor noticeable to others, and/or a history of psychiatric disease or symptoms suggest the possibility of these disorders.

Examples include:

●Olfactory hallucinations – Disorders such as schizophrenia, epilepsy, or central nervous system tumors may induce olfactory hallucinations. (See "Nonepileptic paroxysmal disorders in adolescents and adults", section on 'Olfactory hallucinations'.)

●Olfactory reference syndrome – Olfactory reference syndrome is characterized by an individual's false belief that their body emits an offensive or foul odor [14]. (See "Body dysmorphic disorder: Assessment, diagnosis, and differential diagnosis", section on 'Olfactory reference disorder (olfactory reference syndrome)'.)

The differential diagnosis of bromhidrosis also includes odor unrelated to sweat, such as breath odor (eg, breath odor related to poor dental hygiene, systemic disease, or heavy metal toxicity), clothing odor, or odor associated with wound infection.

TREATMENT — Individuals with bromhidrosis may experience severe impairment in social interactions and quality of life and often seek methods to resolve the condition. The approach to treatment differs for the localized and generalized variants. Data on treatment options for bromhidrosis are limited.

Generalized bromhidrosis — The primary mode of treatment of generalized bromhidrosis is the identification and removal of the underlying cause of bromhidrosis (eg, treatment of the associated systemic disorder, elimination of ingestion of odor-promoting compounds). (See 'Eccrine bromhidrosis' above.)

Suppression of generalized sweating could theoretically be helpful; oral anticholinergic agents, such as glycopyrrolate or oxybutynin, are most commonly used for this purpose. (See "Primary focal hyperhidrosis", section on 'Systemic agents'.)

Localized bromhidrosis — Localized bromidrosis usually results from bacterial degradation of secreted sweat or keratin. Therefore, treatment primarily consists of interventions to reduce bacteria and/or sweating in the affected areas.

Initial treatment — Clinical experience suggests that hygiene adjustments, treatment of contributory skin disorders, and topical antiperspirants may be helpful. We routinely advise these measures as initial therapy in patients presenting with localized bromhidrosis.

Hygiene adjustments — Our typical approach to hygiene advice includes a discussion of bathing frequency, antibacterial cleansers, and clothing.

●Daily washing/bathing – Affected areas should be washed daily. However, excessive washing should be discouraged to avoid skin irritation.

●Use of antibacterial washes/soaps – Products that reduce bacterial colonization in the affected area can be expected to help with odor. Antibacterial washes and bar soaps are widely available.

●Clothing selection and practices – Wearing of absorbent clothing, particularly cotton or materials that wick moisture away from the skin, may be helpful, particularly in the case of socks for foot odor. Perspiration-soaked clothing should be promptly removed, and clothing should be changed at least daily.

●Other measures – Hair may contribute to bromhidrosis through trapping bacteria and odor. Removal of hair in the affected areas through means such as shaving, chemical epilation, or electrolysis may reduce odor, especially in apocrine bromhidrosis. Laser hair removal may be helpful; however, bromhidrosis has occurred as an adverse effect of laser hair removal [11].

Exfoliation to remove excess stratum corneum may reduce odor secondary to bacterial degradation of keratin and may be particularly helpful for foot bromhidrosis.

Treatment of contributory skin diseases — Concomitant skin disorders, such as intertrigo, erythrasma, and pitted keratolysis, may contribute to odor and should be promptly treated. (See "Intertrigo" and "Erythrasma" and "Pitted keratolysis".)

Topical antiperspirants — Reducing the amount of sweat in the affected area may lead to improvement, particularly in patients with eccrine bromhidrosis or with apocrine bromhidrosis in whom hyperhidrosis appears to contribute significantly to malodor.

Topical antiperspirants, most of which are metallic salts with aluminum and zinc, reduce sweating by creating a temporary plug in the sweat duct and are the initial treatment of choice for reducing localized sweating. Aluminum salts are the most common active ingredients in antiperspirants. Metallic salts have other properties that help with odor, including affecting the local pH, and have antimicrobial properties.

Use of antiperspirants is reviewed in detail separately. (See "Primary focal hyperhidrosis", section on 'Treatment'.)

Failure of initial treatment — Treatment options for patients with localized bromhidrosis that does not respond sufficiently to hygiene, treatment of contributor skin diseases, and topical antiperspirants include other sweat-reduction therapies and antimicrobial therapy.

Other sweat-reduction therapies — When hygienic changes and topical antiperspirants are insufficient, use of other sweat-reduction therapies, such as botulinum toxin injections, topical glycopyrrolate (a topical anticholinergic agent), iontophoresis, surgical removal of sweat glands, and other treatments for hyperhidrosis, may be beneficial [15,16]. However, compared with hyperhidrosis, efficacy data for bromhidrosis are limited. Most of the available studies have been performed in patients with axillary bromhidrosis. (See "Primary focal hyperhidrosis", section on 'Treatment'.)

Because high-quality placebo-controlled and comparative trials are lacking, selection among these sweat-reduction therapies is primarily based upon consideration of the site of bromhidrosis, potential adverse effects, patient preference, and treatment availability or feasibility. Reasonable options for axillary bromhidrosis include botulinum toxin injections, topical glycopyrrolate, topical antimicrobial agents, and surgical removal of apocrine glands. Due to the creation of scarring and the potential for surgical complications, we tend to reserve surgical removal of apocrine glands for axillary bromhidrosis that cannot be adequately managed with less invasive interventions.

Given the frequent association of plantar bromhidrosis with hyperhidrosis, our therapeutic approach resembles the approach to hyperhidrosis. (See "Primary focal hyperhidrosis", section on 'Palmar or plantar hyperhidrosis'.)

●Botulinum toxin injections – Neurotoxins, such as botulinum toxin A, are an effective temporary treatment for localized hyperhidrosis that may also be beneficial for bromhidrosis [17-19]. Treatment for hyperhidrosis of localized areas, such as the axillae, scalp, inframammary area, and hands and feet, is considered particularly suitable for neurotoxin injections.

Treatment regimens for bromhidrosis are not standardized; regimens similar to the regimens used for hyperhidrosis are often utilized, with dosing based upon the specific botulinum toxin product utilized. Improvement in bromhidrosis is expected within a few days after treatment. The duration of effect varies, with benefit for bromhidrosis ranging from a few weeks to several months. Injections can be painful; measures to reduce pain may be beneficial (eg, topical anesthetics). (See "Primary focal hyperhidrosis", section on 'Botulinum toxin' and "Primary focal hyperhidrosis", section on 'Botulinum toxin'.)

•In a study of 19 adults with axillary bromhidrosis, participants received a total of 200 units of abobotulinumtoxinA into one randomly assigned axilla and placebo saline injections in the contralateral axilla. Three months after treatment, the mean degree of odor and sweat production were lower in the abobotulinumtoxinA-treated side than in the control axilla (mean degree of odor of 2.4 versus 8.0 on a 10-point scale) [20].

•In a study of 53 adults with recurrent axillary bromhidrosis following surgical or laser removal of apocrine glands who were subsequently treated with botulinum toxin A (at 50 units per axilla), all patients reported dramatic reduction in malodor within four days after treatment, and at six months, 33 of 53 patients reported no recurrence of malodor [21]. The median duration of effect was 6 months (range 1 to 12 months).

Reductions in sweating and axillary odor have also been reported in patients without true bromhidrosis [19].

Sequential treatments may be associated with increased duration of effect. In an uncontrolled study of 62 adolescents with axillary bromhidrosis treated with botulinum toxin A (at 50 units per axilla), 38 patients were free of odor for a period of at least 4 weeks (median 24 weeks) after a single injection session, and among 21 of these patients who received a second injection, the median duration of efficacy was 28 weeks [22]. Among patients who received a third (eight patients) and fourth injection (four patients), mean durations of effect were 32 and 36 weeks, respectively.

●Topical glycopyrrolate – Topical glycopyrrolate (glycopyrronium) is used for hyperhidrosis and may be beneficial for bromhidrosis. Topical glycopyrrolate has been best studied for axillary hyperhidrosis but may be helpful for palmar hyperhidrosis as well [23]. (See "Primary focal hyperhidrosis", section on 'Topical glycopyrronium' and "Primary focal hyperhidrosis".)

In an uncontrolled study, 19 patients with bromhidrosis applied glycopyrronium bromide 2% cream to the axillae nightly for 12 weeks [24]. After treatment, the number of patients reporting moderate or severe malodor fell from 18 to 2.

Potential adverse effects include local skin irritation and anticholinergic symptoms.

●Iontophoresis – Clinical experience suggests that iontophoresis, a treatment for hyperhidrosis that uses electrical current to inhibit sweating, may also be beneficial for bromhidrosis. Iontophoresis is primarily used for palmar or plantar bromhidrosis that is associated with hyperhidrosis. (See "Primary focal hyperhidrosis", section on 'Iontophoresis' and "Primary focal hyperhidrosis", section on 'Iontophoresis'.)

●Surgical apocrine gland removal – Destruction or removal of axillary apocrine glands via various surgical excision techniques or liposuction may be beneficial for apocrine bromhidrosis involving the axillae. These therapies are often reserved for axillary bromhidrosis that is refractory to nonsurgical interventions because of the expected outcome of scarring and the potential for other surgical complications. (See "Primary focal hyperhidrosis", section on 'Suction curettage'.)

Data from uncontrolled studies suggest that surgical excision or liposuction to remove axillary apocrine glands can result in improvement in a majority of patients [15,16,25]. Examples of some of the largest studies include:

•In one of the largest studies of surgical excision, a subcutaneous gland excision technique was performed in 256 adult and adolescent patients with axillary bromhidrosis [26]. In the assessment of the 206 patients who had at least three months of follow-up, 398 of 412 axillae (97 percent) had "good" malodor elimination (ie, neither the patient nor others near the patient could detect malodor even during sweating). The most common complications included transient superficial epidermal necrosis in 152 axillae (37 percent), wound dehiscence in 21 axillae (5 percent), seroma in 5 axillae (1 percent), and comedones in 5 axillae (1 percent).

•In an uncontrolled study of a modified liposuction-curettage technique performed in 80 patients with axillary bromhidrosis, patients reported excellent malodor elimination (neither the patient nor close friends were aware of malodor) in 141 of 157 axillae (90 percent) [27]. Postoperative complications included local epidermal damage in 28 axillae (18 percent), a small area of skin necrosis in 4 axillae (3 percent), and hematoma in 1 axilla (1 percent).

•In an uncontrolled study of subcutaneous curettage combined with trimming performed in 158 adults with axillary bromhidrosis, patients reported excellent malodor elimination (no odor after intense exercise) in 264 out of 300 axillae (88 percent) six months after treatment [28]. Postoperative complications included ecchymoses in 19 patients (6 percent) and hematoma in 4 patients (1 percent).

●Other therapies – Small uncontrolled studies also suggest benefit of apocrine gland destruction via subcutaneous neodymium-doped yttrium aluminum garnet (Nd:YAG) laser therapy [29-31], subcutaneous carbon dioxide (CO₂) laser ablation [32,33], or microwave thermolysis [34,35] in bromhidrosis. However, further study is necessary to confirm efficacy and appropriate regimens [15,16]. (See "Primary focal hyperhidrosis", section on 'Microwave thermolysis'.)

Thoracic sympathectomy may also be effective for refractory axillary bromhidrosis but may be most beneficial for patients with accompanying hyperhidrosis [36]. (See "Primary focal hyperhidrosis", section on 'Sympathectomy'.)

Topical oxybutynin, sofpironium bromide, and umeclidinium are under investigation for hyperhidrosis and may be potential treatments for bromhidrosis [37].

Topical antimicrobial agents — The role of bacteria in the formation of malodorous compounds causing bromhidrosis is well established, and clinical experience suggests that reducing bacteria through antimicrobial agents can improve odor, even in the absence of overt skin infection.

Various antimicrobial agents have been used in clinical practice. Benzoyl peroxide washes (used daily), topical erythromycin (applied twice daily), and topical clindamycin (applied twice daily) are reasonable choices. Data from a small noncontrolled study suggest benefit of a silver-based topical bactericidal agent (silver-exchanged zeolite) for reducing axillary odor [38].

Repeated or continuous treatment with topical antimicrobial agents may be necessary to maintain improvement.

Other interventions — Other products or ingredients have been proposed to help reduce malodor in localized bromhidrosis. Examples include systemic antibiotic therapy based upon culture results from the affected region and topical formulations that affect the pH of the affected area. Topical acids (eg, alpha- and beta-hydroxy acids) and bases (eg, baking soda) may be helpful, though skin irritation may develop.

There are also various deodorants and other products advertised as having natural ingredients that may have antibacterial or other properties that decrease odor. Rubbing one-half a lemon directly on the area has been used by some individuals. Apple cider vinegar and witch hazel are other natural deodorants. Charcoal-based topicals may also help absorb odor-causing chemicals.

SUMMARY AND RECOMMENDATIONS

●Disease overview – Bromhidrosis describes the occurrence of excessively foul-smelling sweat. The disorder is divided into apocrine and eccrine subtypes based upon the type of sweat gland involved. (See 'Classification' above.)

•Apocrine bromhidrosis – Apocrine bromhidrosis is a localized form of bromhidrosis that occurs in sites with significant numbers of apocrine glands (eg, axillae, anogenital region, or breasts). Malodor typically results from bacterial degradation of fatty acids secreted in apocrine sweat. (See 'Pathogenesis' above.)

•Eccrine bromhidrosis – Eccrine bromhidrosis may be localized or generalized. Localized eccrine bromhidrosis usually occurs in sites where sweating leads to skin maceration and subsequent bacterial degradation of keratin. The feet are common sites. Generalized eccrine bromhidrosis typically results from systemic illness or ingestion of or exposure to odor-promoting substances. (See 'Pathogenesis' above.)

●Clinical presentation – The odor of bromhidrosis is often described as "rancid," "pungent," or "sour."

●Diagnosis – The diagnosis usually can be made by smelling affected skin and obtaining a history of malodor noted by the patient and other individuals. Activity to induce sweating (exercise, exposure to heat) may be helpful for diagnosis when odor is not immediately apparent.

Once bromhidrosis is confirmed, patients should be evaluated for potential exacerbating or causative factors. Potential contributors to localized bromhidrosis include hyperhidrosis, insufficient hygiene, and concomitant cutaneous disorders. Recognition of the type of odor, assessment of the patient's medical history and review of systems, performance of a physical examination, and/or selection of appropriate laboratory tests can be helpful for identifying disorders contributing to generalized bromhidrosis. (See 'Clinical presentation' above and 'Diagnosis' above.)

●Treatment

•Generalized bromhidrosis – Identification and removal of the underlying cause of bromhidrosis (eg, treatment of the associated systemic disorder, elimination of exposure to odor-promoting compounds) is the primary mode of treatment for generalized bromhidrosis. (See 'Generalized bromhidrosis' above.)

•Localized bromhidrosis – The treatment of localized bromhidrosis focuses on improving hygiene and reducing bacteria and sweating in the affected area. For patients with localized bromhidrosis, initial management includes skin hygiene, absorbent clothing, and topical antiperspirants and deodorants. In addition, associated cutaneous diseases such as intertrigo, erythrasma, and pitted keratolysis should be treated. (See 'Treatment' above.)

When these measures are insufficient, options include use of other sweat-reduction techniques (eg, botulinum toxin injections, topical anticholinergic agents, iontophoresis, surgical removal of axillary apocrine glands) and topical antimicrobial agents. Because of limited efficacy data, selection among these interventions is primarily based upon consideration of the site of bromhidrosis, potential adverse effects, patient preference, and treatment availability or feasibility. (See 'Failure of initial treatment' above.)

-Axillary bromhidrosis – For axillary bromhidrosis with an insufficient response to hygiene measures, topical antiperspirants, and treatment of associated cutaneous disease, we suggest a trial of less invasive therapies prior to surgical removal of apocrine glands (Grade 2C). Options for less invasive therapy include botulinum toxin injections, topical anticholinergic agents, and topical antimicrobial agents. However, surgical removal of apocrine glands is a reasonable alternative when these interventions are not feasible or when patients prefer a surgical approach to therapy. (See 'Failure of initial treatment' above.)

-Plantar bromhidrosis – Given the frequent association of plantar bromhidrosis with hyperhidrosis, our approach to treatment selection resembles the approach to hyperhidrosis. (See "Primary focal hyperhidrosis", section on 'Palmar or plantar hyperhidrosis'.)