Renal colic abdominal pain results in microcytic lung neoplasm… whatelse?

A 73-year-old man with cardiovascular risk factors (arterial hypertension, dyslipidemia, and cigarette smoking) presented to the emergency department with a 24-hours history of right lumbar pain, positive right fist percussion, fever and renal failure. An urgent ultrasound was performed to discard acute renal complications. Ultrasound showed grade III righthydronephrosis, without being able to visualize the cause due to the presence of abundant intestinal gas. Subsequently, a computed tomography (CT) was performed.The CT showed a left hilar mass which narrowed the superior left pulmonary vein, the left upper artery and the left upper bronchus. Large mediastinal and axillary nodes were also visible. In abdominal images, grade III right hydronephrosis was confirmed. The cause happened to be a pelvic node metastases which encased the distal ureter. Multiple irregular intrabdominal nodes were also seen, compatible with neoplastic implants, as well as celiac axis and paraaortic size-increased lymph nodes. Finally, suprarenal glands appeared enlarged and hypodense, suggestive of metastasic disease.

Lumbar pain is a usual reason for referral to emergency departments. The cause is frequently nonspecific, and the clinical course is often favorable. In the majority of patients, pain disappears with or without treatment in a few weeks. But in some cases, as the case presented, a severe illness can lie behind. All the CT findings were in relation with disseminated primary lung neoplasia.

Ultrasound is the primary imaging technique in patients with renal colic pain in the emergent setting. It is noninvasive, fast, portable and gives information on the degree of kidney pelvicalyceal affection. However, it may present limitations (such as gas interposition and interobserver variability). In these cases, CT is a crucial imaging technique and has become the standard of reference in the detection of urinary calculi, and to outline alternative causes of low back pain when ultrasound is limited.

- Maher C, Underwood M, Buchbinder R. Non-specific low back pain. Lancet 2017, 389: 736-47. - Rucker CM, Menias CO, Bhalla S. Mimics of Renal Colic: Alternative Diagnoses at Unenhanced Helical CT. Radiographics 2004, 24: S11-28.