Obstructive causes
BPH
Prostate cancer
Blood clot
Urethral Stricture
Bladder Calculi
Bladder neoplasm
Foreign body, urethral or bladder
Ovarian/uterine tumor
Incarcerated uterus
Neurogenic causes
Multiple sclerosis
Parkinson's
Brain tumor
Cerebral vascular disease
Cauda equina syndrome
Spinal cord compression (non-traumatic)
Intervertebral disk herniation
Neuropathy
Nerve injury from pelvic surgery
Postoperative<unk> 
Trauma
Urethral injury
Bladder injury
Spinal cord injury
Extraurinary causes
Perirectal or pelvic abscesses
Rectal or retroperitoneal masses
Fecal impaction
Abdominal Aortic Aneurysm
Psychogenic causes
Psychosexual stress<unk>  anxiety
Infection
Cystitis
Prostatitis
Herpes Simplex (genital)
Herpes Zoster involving pelvic region
Local Abscess
PID
Meds
Anticholinergics
Antihistamines
Cold meds
Sympathomimetics
TCA
Muscle relaxants
Opioids
BPH
Prostate cancer
Blood clot
Urethral Stricture
Bladder Calculi
Bladder neoplasm
Foreign body, urethral or bladder
Ovarian/uterine tumor
Incarcerated uterus
Multiple sclerosis
Parkinson's
Brain tumor
Cerebral vascular disease
Cauda equina syndrome
Spinal cord compression (non-traumatic)
Intervertebral disk herniation
Neuropathy
Nerve injury from pelvic surgery
Postoperative<unk> 
Urethral injury
Bladder injury
Spinal cord injury
Perirectal or pelvic abscesses
Rectal or retroperitoneal masses
Fecal impaction
Abdominal Aortic Aneurysm
Psychosexual stress<unk>  anxiety
Cystitis
Prostatitis
Herpes Simplex (genital)
Herpes Zoster involving pelvic region
Local Abscess
PID
Anticholinergics
Antihistamines
Cold meds
Sympathomimetics
TCA
Muscle relaxants
Opioids
Obesity
Intestinal obstruction
Pregnancy
Ascites
Cirrhosis
Malignancy
Heart failure
Tuberculosis
Spontaneous bacterial peritonitis
Peritoneal dialysis-associated peritonitis
Distended bladder /<unk> 
Constipation / fecal impaction
Large tumor(s) (e.g. ovarian, lymphoma)
Organomegaly
Cirrhosis
Malignancy
Heart failure
Tuberculosis
Acute urinary retention
Obstructive causes
Acute cystitis
BPH
Diabetes insipidus
Prostate cancer
TURP syndrome
Blood clot