The main symptoms of BPS/IC can be similar to multiple different pelvic pain conditions – confusable diseases. The confusable diseases that explain the symptoms should be ruled out to prevent misdiagnosis or over-diagnosis of BPS.

Diseases that may display similar symptoms to BPS

• Recurrent urinary tract infections (UTI)
• Infections (bacteria, Tuberculosis, Herpes, Chlamydia, Vaginal candidiasis)
• Overactive bladder
• Endometriosis
• Bladder stones or bladder neck obstruction
• Urethral diverticulum (outpouching)
• Urethral stricture
• Masses near the urethra (Skene gland cyst or abscess)
• Carcinoma and carcinoma in situ
• Radiation cystitis
• Pelvic prolapse
• Pudendal neuralgia (neuropathy)
• Pelvic floor (dysfunctions) hypertonic disorders
• Epididymitis
• Gynaecologic diseases

For frequency and urgency, there is additional list as some of the causes:

• Habit
• Large post-void residual
• Genital condyloma
• Periurethral gland infection
• Chemical irritants
• Detrusor instability
• Diuretic therapy
• Pelvic mass
• Chemotherapy
• Bacterial urethritis
• Atrophic urethral changes

Relevant comorbidities

Bladder pain syndrome frequently overlaps medical conditions and neurological diseases (relevant comorbidities) because of nerve and vascular connections between pelvic organs. The overlapping of symptoms can lead to delay of diagnosis, misdiagnosis and often to inadequate treatment. Therefore a multidisciplinary approach to treatment of BPS is recommended.

Medical diseases:

• Diabetes mellitus or insipidus,
• Renal diseases,
• Heart failure,
• Thyroid diseases

Neurological diseases:

• Parkinson’s disease,
• Multiple sclerosis,
• Cerebrovascular disease,
• Radiculopathy
• Spinal cord injury
• Prolapsed intervertebral disc with impingement on the spinal cord
• Upper motor neuron lesion

Orthopedic diseases:

• Pubic symphysis instability
• Pelvic joint dysfunction
• History of pelvic trauma, surgery