What is the cause of nocturnal hyperhidrosis in a 3 year and 9 month old boy recovering from a upper respiratory tract infection (cold) without fever, with a resolved mild cough and no sneezing?

Differential Diagnosis for a 3 Year and 9 Month Old Boy with Night Sweats

• Single Most Likely Diagnosis + Overheating or inappropriate sleep environment: This is the most likely cause, as the child is recovering from a cold and may have been overdressed or have a warm sleep environment, leading to excessive sweating.
• Other Likely Diagnoses + Normal variation in sweat response: Some children may naturally sweat more than others, especially during sleep. + Sleep-associated anxiety or stress: The child may be experiencing anxiety or stress that is causing him to sweat excessively during sleep. + Respiratory infection sequelae: Although the child has recovered from the cold, some residual inflammation or congestion may be contributing to the night sweats.
• Do Not Miss Diagnoses + Tuberculosis (TB): Although unlikely, TB can cause night sweats, and it is essential to consider this diagnosis, especially if the child has been exposed to someone with TB. + Lymphoma or other malignancies: Night sweats can be a symptom of certain types of cancer, such as lymphoma, and it is crucial to rule out these diagnoses. + Infectious diseases (e.g., endocarditis, osteomyelitis): Certain infectious diseases can cause night sweats, and it is essential to consider these diagnoses, especially if the child has a history of recurrent infections.
• Rare Diagnoses + Hyperthyroidism: This condition can cause excessive sweating, including night sweats, although it is rare in children. + Pheochromocytoma: A rare tumor that can cause excessive sweating, including night sweats, due to excessive catecholamine production. + Neurological disorders (e.g., autonomic dysfunction): Certain neurological disorders can affect the autonomic nervous system, leading to excessive sweating, including night sweats.