Idiopathic Edema: This condition is characterized by swelling of the hands, feet, and face without an identifiable cause. It is relatively common in adolescents and young adults, particularly females. The swelling typically resolves on its own throughout the day.

Juvenile Idiopathic Arthritis (JIA): Although JIA can cause joint swelling, it is often accompanied by other symptoms such as joint pain, stiffness, and limited range of motion. Morning swelling is a common feature.
Premenstrual Water Retention: Hormonal changes during the menstrual cycle can lead to water retention, causing swelling in the hands, feet, and face.
Allergic Reactions: Allergic reactions to certain foods, medications, or environmental factors can cause swelling, although this would typically be accompanied by other symptoms such as rash, itching, or respiratory issues.

Systemic Lupus Erythematosus (SLE): A chronic autoimmune disease that can cause swelling, particularly in the hands and feet, as well as other systemic symptoms such as fever, fatigue, and joint pain. Early diagnosis is crucial to prevent long-term damage.
Thyroid Disorders: Both hypothyroidism and hyperthyroidism can cause swelling in the hands and feet, among other symptoms. Thyroid function tests are essential to rule out these conditions.
Kidney Disease: Certain kidney diseases, such as nephrotic syndrome, can cause edema due to protein loss in the urine. This would be accompanied by other symptoms such as foamy urine and weight gain.

Scleroderma: A chronic autoimmune disease characterized by thickening of the skin and connective tissue, leading to swelling and limited mobility in the hands and feet.
Ehlers-Danlos Syndrome: A genetic disorder affecting connective tissue, which can cause joint hypermobility, skin hyperextensibility, and tissue fragility, potentially leading to swelling.
Lymphedema: A condition characterized by chronic swelling due to impaired lymphatic drainage, which can be primary (inherited) or secondary (acquired).