What could be causing a feeling of swelling in the genital area, necessitating a wide-based gait, that worsens upon standing?

Genital Swelling with Wide-Based Gait Worsening on Standing

The most likely diagnosis is pelvic organ prolapse causing vaginal/vulvar fullness and pressure, which requires pelvic examination to assess the degree of prolapse and determine if conservative management (pessary, pelvic floor therapy) or surgical referral is appropriate.

Immediate Red Flag Assessment

Before considering benign causes, urgent conditions must be excluded:

• Bartholin gland abscess presents with unilateral swelling, erythema, and tenderness at the 4 or 8 o'clock position of the posterior vestibule, potentially extending into the entire labia minora 1
• Fournier's gangrene manifests as painful swelling of the perineum with sepsis, requiring immediate surgical debridement and broad-spectrum antibiotics; up to 40% of cases have insidious onset with undiagnosed pain 1
• Genital lymphedema increases relative risk of cellulitis and requires evaluation for acute infection 2

Most Likely Diagnosis: Pelvic Organ Prolapse

The symptom constellation of genital fullness/swelling sensation, wide-based gait, and worsening with standing is classic for pelvic organ prolapse:

• Gravitational worsening is pathognomonic—symptoms improve when lying down and worsen throughout the day with standing [@general medical knowledge@]
• Wide-based gait occurs as patients compensate for the sensation of "something falling out" or bulging [@general medical knowledge@]
• Physical examination should assess for cystocele, rectocele, uterine prolapse, or vaginal vault prolapse by having the patient bear down during speculum examination 1

Differential Diagnoses to Consider

Infectious/Inflammatory Causes

• Bartholin gland infection: Commonly infected by STI pathogens including gonorrhea and chlamydia; presents with swelling, erythema, and tenderness 1
• Genital lymphedema: Chronic condition causing persistent swelling; diagnosis often delayed due to embarrassment and lack of clinical confidence 2
• Crohn's disease with metastatic genital involvement: In 88% of cases, cutaneous symptoms precede formal CD diagnosis; requires evaluation for underlying inflammatory bowel disease 3

Anatomical/Structural Causes

• Imperforate hymen in pubertal females causes accumulation of blood in the vagina and upper genital tract, requiring prompt gynecologic referral 1
• Penoscrotal lymphedema (if male patient): Characterized by extreme discomfort with limitation of hygiene, ambulation, sexual intercourse, and voiding in standing position 4

Diagnostic Approach

External genitalia examination should assess for:

• Signs of inflammation including redness or swelling 1
• Bartholin glands at 4 and 8 o'clock positions for swelling, erythema, tenderness 1
• Pigmentary changes suggesting lichen sclerosus or vitiligo 1
• Any lesions, trauma, or discharge 1

Speculum examination (if appropriate) to:

• Assess degree of pelvic organ prolapse with Valsalva maneuver 1
• Evaluate vaginal walls and cervix for abnormalities 1

Laboratory testing if infection suspected:

• Culture/antigen tests for STIs: chlamydia, gonorrhea, trichomonas 1
• Gram stain of any discharge 5

Management Algorithm

If Pelvic Organ Prolapse Confirmed:

• Conservative management: Pelvic floor physical therapy, pessary fitting [@general medical knowledge@]
• Surgical referral: For symptomatic prolapse affecting quality of life [@general medical knowledge@]

If Bartholin Gland Infection:

• Empiric antibiotics: Ceftriaxone 1 g IM/IV plus doxycycline 100 mg orally twice daily for 10 days 1, 5
• Surgical drainage: If abscess formation present 5

If Genital Lymphedema:

• Supportive measures: Compression, elevation, skin care to prevent cellulitis 2
• Surgical treatment: Modified Charles procedure for severe cases affecting quality of life 4

Common Pitfalls to Avoid

• Do not delay surgical consultation for suspected Fournier's gangrene or abscess formation requiring urgent intervention 1
• Do not miss Crohn's disease: In boys with unexplained genital swelling, evaluation for CD is necessary as genital swelling typically precedes intestinal symptoms 3
• Do not attribute all genital swelling to infection: Consider anatomical causes like prolapse, especially when symptoms worsen with standing and improve with lying down [@general medical knowledge@]
• Do not force pelvic examination: All efforts should be made to perform examination in office setting, but forcing a patient to undergo pelvic examination is always contraindicated 1