Case

A 58 year-old male, with history of kidney stones and appendectomy, presents to the ED with complaint of left lower quadrant abdominal pain. The patient goes on to describe waxing and waning “deep” and moderately severe pain in the abdomen with radiation to the back for two days. He notes associated nausea and one episode of dark urine but denies any fevers, nausea, vomiting, diarrhea, or any other urinary symptoms. He reports the pain is similar to prior episode of kidney stones, but feels more anterior.

Vital Signs

BP 177/93 | Pulse 87  | Temp 98.1 °F (36.7 °C)  | Resp 20  | SpO2 97%

Exam
Constitutional: Well-developed, in no apparent distress.

Cardiovascular: Normal rate and regular rhythm.  

Pulmonary/Chest: Effort normal and breath sounds normal. He has no wheezes. He has no rales.

Abdominal: Soft. Focal left local quadrant tenderness, No rebound, rigidity or guarding.  

GU: Normal testicular lie, no tenderness or erythema of the testicles. Normal cremasteric reflex. No costovertebral angle  tenderness.

Workup

Labs performed including complete blood count and basic metabolic profile are within normal limits, with a creatinine of 0.74. Urinalysis demonstrates 10 red blood cells, 1 white bell cells, and is otherwise within normal limits.

Given the patient’s significant abdominal pain, Computed tomography (CT) abdomen/pelvis with contrast is performed:

Diagnosis

Spontaneous calyceal rupture

Radiologic impression

Mild left hydronephrosis, with moderate to severe perinephric and lower left retroperitoneal fluid concerning for recent calyceal rupture. No discrete obstructing calculus currently visualized. Of note, there is a 1.1 cm calculus in the left renal pelvis. In addition, given, extensive fluid, superimposed infection cannot be excluded.

Discussion

The above case is a classic example of a not-too-common urologic finding in the ED: spontaneous calyceal rupture. This finding is thought to occur as a result of a sudden increase in pressure in the collecting system. Most commonly, this sudden increase pressure is due to an obstructing kidney stone (typically in the distal ureter), however, it has also been described in the setting of other pathologies that obstruct the urinary system, including cancer, prostatic hypertrophy, pregnancy, and abdominal aortic aneurysm, as well as iatrogenic causes. The collecting system, typically a low-pressure system, is poorly equipped to handle the sudden increase in pressure, and ruptures in the most susceptible part of the system — the calyx. More specifically, it is the fornix, the lateral aspect of the minor calyx, that is the most common culprit (Figure 1).

Most cases of calyceal rupture present with flank pain, nausea, and vomiting, although more severe symptoms, such as severe abdominal pain and systemic findings, can occur. Rupture results in extravasation of urine that can collect around kidney or even in the retroperitoneum. The feared complication of this process is infection of the urine collection, leading to perinephric abscess formation and sepsis. The diagnosis is made either via ultrasound or CT.

Management first involves relieving the cause of obstruction. In the ED, if the obstruction is secondary to prostatic hypertrophy a foley should be placed. The patient should receive hydration and analgesia. Urology should be consulted to understand which patients will need intervention such as stenting or lithotripsy. At this time there is no standard as to the appropriateness of antibiotic therapy. Of course, if a patient shows evidence of infection, antibiotics (and source control) are indicated. However, if a patient demonstrates no systemic signs of infection and has a negative urinalysis it is reasonable to consider deferring antibiotics at the index visit. This decision, as well as whether to admit or discharge the patient should be made in conjunction with our urology colleagues.

Case conclusion

The patient was managed conservatively with fluids and analgesia. Antibiotics were deferred in consultation with Urology. The patient was discharged to close urologic follow-up. At four month chart review the patient had suffered no further complications and no long term sequelae from his calyceal rupture.  

 Faculty Reviewer: Dr. Kristy McAteer

References

1. Al-Mujalhem AG, Aziz MS, Sultan MF, Al-Maghraby AM, Al-Shazly MA. Spontaneous forniceal rupture: Can it be treated conservatively? Urol Ann 2017:9(1);41-44 

2. Doehn C, et al. Outcome analysis of fornix ruptures in 162 consecutive patients. J Endourol 2010;24(11):1869-73.

3. Morgan TN, Bandari J, Shahait M, Averch T. Renal forniceal rupture: Is conservative management safe? Urology 2017;109:51-54.

4. Tanwar S, Joshi A. A blow-out. Am J of Med 2011;124(1):37-39.

5. https://opentextbc.ca/anatomyandphysiology/chapter/25-3-gross-anatomy-of-the-kidney/