Primary Nocturnal Enuresis: This is the most common cause of nocturia in children, characterized by the involuntary voiding of urine during sleep in children over 5 years old. It is often related to a combination of factors, including genetics, bladder control issues, and hormonal imbalances.

Constipation: Constipation can cause urinary frequency and nocturia due to the pressure exerted by the full bowel on the bladder.
Urinary Tract Infections (UTIs): UTIs can cause irritation to the bladder, leading to frequent urination, including at night.
Diabetes Mellitus: Uncontrolled diabetes can lead to polyuria (excessive urine production), resulting in nocturia.
Obstructive Sleep Apnea (OSA): OSA can increase the production of urine at night due to increased pressure on the heart and subsequent release of atrial natriuretic peptide.

Diabetes Insipidus: A condition characterized by the inability to regulate fluids in the body due to problems with the antidiuretic hormone (ADH), leading to excessive thirst and urination.
Kidney Disease: Chronic kidney disease can cause a range of urinary symptoms, including nocturia, due to the kidneys' reduced ability to concentrate urine.
Neurological Disorders: Conditions such as spina bifida, spinal cord injuries, or neurological diseases (e.g., multiple sclerosis) can affect bladder control, leading to nocturia.
Sleep Disorders: Besides OSA, other sleep disorders can disrupt normal sleep patterns and increase the likelihood of nocturia.

Nocturnal Seizures: In some cases, nocturia can be a manifestation of nocturnal seizures, which occur during sleep.
Bladder or Urethral Anomalies: Congenital anomalies of the bladder or urethra can lead to urinary symptoms, including nocturia.
Endocrine Disorders: Other than diabetes, certain endocrine disorders (e.g., hyperthyroidism) can cause increased urine production.
Psychogenic Polydipsia: A condition where an individual drinks excessive amounts of water, leading to polyuria and nocturia, often associated with psychological factors.