History of Present Illness (HPI)

The patient is a child who has been experiencing left flank pain for one week. The pain is accompanied by upper back pain. The onset of pain coincides with the child getting a new trampoline and increasing their jumping activity. The child denies any symptoms suggestive of a urinary tract infection (UTI), such as dysuria, frequency, or urgency. However, the mother is concerned about the possibility of a kidney infection due to the nature of the pain.

Differential Diagnosis

• Single Most Likely Diagnosis
  • Musculoskeletal strain: Given the recent increase in trampoline activity, it is likely that the child has developed a musculoskeletal strain, particularly in the back and flank area, due to overuse or improper landing techniques.
• Other Likely Diagnoses
  • Costochondritis: The child's upper back pain and flank pain could be related to costochondritis, an inflammation of the cartilage that connects the ribs to the breastbone, which can be exacerbated by physical activity.
  • Scheuermann's disease: This condition, characterized by an abnormal curvature of the spine, could cause upper back pain and might be exacerbated by jumping activities.
• Do Not Miss Diagnoses
  • Kidney stone: Although the child denies UTI symptoms, a kidney stone could cause severe flank pain and must be considered, especially if the pain is severe and persistent.
  • Pyelonephritis: Despite the denial of UTI symptoms, pyelonephritis (a kidney infection) is a serious condition that requires prompt diagnosis and treatment. It can present with flank pain and might not always have typical UTI symptoms, especially in children.
  • Spinal fracture or injury: Given the trampoline use, there is a risk of spinal injury, including fractures, which could present with back and flank pain.
• Rare Diagnoses
  • Nephroblastoma (Wilms tumor): A rare kidney cancer that can cause flank pain and is more common in children.
  • Osteoid osteoma: A benign bone tumor that can cause night pain and might be considered if the pain persists and other diagnoses are ruled out.

Each diagnosis is considered based on the combination of the child's symptoms, recent activities, and the potential risks associated with those activities. The justification for each category is based on the likelihood of the condition given the clinical presentation and the need to rule out serious or life-threatening conditions.