How to manage burning micturition in a patient with pemphigus vulgaris?

Management of Burning Micturition in Pemphigus Vulgaris

Burning micturition in pemphigus vulgaris indicates urogenital mucosal involvement and requires immediate evaluation for infection followed by symptomatic relief with phenazopyridine while optimizing systemic immunosuppression to control the underlying autoimmune disease.

Immediate Assessment and Infection Exclusion

• Obtain bacterial and viral swabs from any visible urogenital erosions to rule out secondary infection, as infection and sepsis are significant risks and major causes of mortality in pemphigus vulgaris 1, 2
• Send urine culture and urinalysis to exclude urinary tract infection, which can present with identical burning symptoms 1
• If local or systemic signs of infection are present, initiate systemic antibiotics according to local policy before proceeding with other interventions 1

Symptomatic Relief

• Prescribe phenazopyridine 200 mg three times daily for symptomatic relief of burning, urgency, and discomfort arising from mucosal irritation, not to exceed 2 days of treatment 3
• Phenazopyridine provides analgesic action to the urinary tract mucosa and is compatible with both antibacterial and immunosuppressive therapy 3
• Many patients with pemphigus report pain or burning sensations during mucosal involvement; offer systemic analgesia as needed, with attention to both acute and maintenance pain control 1

Optimization of Systemic Immunosuppression

• If the patient is not already on adequate systemic therapy, initiate oral prednisolone at 1 mg/kg/day combined with azathioprine 2-3 mg/kg/day (if TPMT normal) or mycophenolate mofetil 2-3 g/day in divided doses 2, 4
• For patients already on treatment who develop new mucosal symptoms, this represents inadequate disease control and requires escalation of therapy 1
• If no response within 5-7 days on prednisolone 1 mg/kg/day, increase the dose in 50-100% increments until disease control is achieved 2
• Disease control is defined as no new lesions and onset of healing in pre-existing lesions, typically achieved within 3 weeks 1, 2

Management of Mucosal Erosions

• Gently cleanse affected areas with antimicrobial solution using aseptic technique 1
• Apply nonadherent dressings if necessary to protect erosions 1
• Daily washing with antibacterial products can decrease colonization and reduce infection risk 1

Common Pitfalls to Avoid

• Do not delay definitive immunosuppressive treatment while providing only symptomatic relief, as phenazopyridine only masks symptoms without treating the underlying autoimmune process 3
• Avoid premature tapering of corticosteroids before disease control is established and consolidated, as this increases relapse risk 1, 2
• Be aware that azathioprine and mycophenolate mofetil have a latent period of 6-8 weeks before therapeutic effects are seen, so immediate symptom control requires adequate corticosteroid dosing 1, 2
• Maintain high vigilance for signs of infection throughout treatment, as infection-related mortality remains a major concern in pemphigus vulgaris 1, 4

Treatment Escalation for Refractory Cases

• If burning micturition persists despite 3 weeks of prednisolone 1.5 mg/kg/day or 12 weeks of adequate adjuvant immunosuppression, this constitutes treatment failure 2
• Consider switching to the alternate steroid-sparing agent (azathioprine ↔ mycophenolate mofetil) 2, 4
• For severe refractory mucosal disease, rituximab combined with short-term corticosteroids achieves 89% complete remission off all treatment at 2 years, with clinical improvement typically beginning within 6 weeks 4, 5