Article, Urology

Idiopathic renal infarction in a young woman

Correspondence

Idiopathic Renal infarction in a young woman

To the Editor,

Renal infarction is an uncommon disease that may mimic renal colic in its presentation and if undiagnosed can lead to significant morbidity. Until recently, intravenous pyelogram (IVP) was the diagnostic study of choice in the ED evaluation of suspected renal colic. However, IVP has increasingly been replaced by unenhanced helical computed tomography (CT) scans. The following case illustrates the limitations of performing a structural rather than functional diagnostic test in the evaluation of renal colic.

A 42-year-old woman presented to the ED with a chief complaint of several days of intermittent left flank pain radiating to the left lower abdominal quadrant. She denied trauma, fever, palpitations, or hematuria. She initially sought treatment from her primary care physician, who prescribed a Muscle relaxant that brought no relief. Physical examination revealed a blood pressure of 140/90, regular pulse rate, and she was afebrile. There was mild left lower quadrant abdominal tenderness but no costovertebral angle tender- ness. Initial treatment included intravenous (IV) hydration and analgesia, with incomplete pain relief. Urinalysis was negative for protein, nitrates, and Leukocyte esterase, and microscopically showed 17 red blood cells per high-power field (hpf), 36 white blood cells per hpf, and 1074 bacteria per hpf. Renal function and electrolytes were normal and white blood cell count was 11,700/mm3. Helical unenhanced CT scan failed to show nephrolithiasis or other abnormali- ties. As the patient was having persistent pain, a double- contrast abdominal CT was performed and revealed areas of discretely diminished perfusion consistent with a left renal infarction. She was admitted to the hospital for pain control and diagnostic evaluation. magnetic resonance angiography of the abdomen demonstrated left renal infarction and normal abdominal aorta and renal arteries. Doppler ultrasound of the lower extremities showed no evidence of deep venous thrombosis. Hypercoagulable workup, including factor V, protein C, Protein S, C3, C4, phosphaditylserine antibodies, anticardiolipin antibody, and antiphospholipid antibody, was negative. Serum cholesterol and triglycerides were 129 and 39, respectively. Serum Lactate dehydrogenase

peaked at 428. Serum antinuclear antibody titer was borderline elevated at 1:80 (reference range, b1:80). Serum aspartate aminotransferase and alanine aminotransferase remained normal. Echocardiogram showed no evidence of thrombus, although there was an equivocal patent foramen ovale. The patient was discharged 3 days later on Warfarin therapy, with preserved renal function, and a diagnosis of idiopathic renal infarction.

Renal infarction is ban uncommon mimic presenting with flank painQ [1]. Although uncommon, it is important to think of renal infarction as an etiology for otherwise unexplained flank pain. Although an IVP would also reveal a renal infarction as the cause of a patient’s flank pain, an un- enhanced CT would not, thus leading to a possible missed diagnosis. It is important to pursue alternative diagnostic modalities in a patient with no evidence of renal calculus and ongoing flank pain, rather than to assume that a calculus has passed.

The patient described in this case had microscopic hematuria, elevated LDH, and leukocytosis, all commonly found in renal infarction [2,3]. Renal infarction usually occurs in elderly patients with risk for atheromatous plaques. Other etiologies include emboli, fibromuscular dysplasia (especially in young women), Renal artery dissection, vasculitis, trauma, and hypercoagulability. The usual Imaging study for suspected urinary tract calculi, unenhanced spiral CT, would not identify renal infarction. Computed tomography with IV contrast is a sensitive and specific study for the diagnosis of renal infarction. The major complication of renal infarction is hypertension and renal failure and the other risks associated with the etiology of the renal infarct. This patient was started on warfarin therapy. Although incidences are rare, previous studies have shown that anticoagulation is as effective as surgical therapy, and Conservative therapy is recommended except in cases where bilateral emboli or infarction of a solitary kidney has occurred [4]. Patients presenting with brenal colicQ and a negative unenhanced CT should be evaluated for renal infarction [5,6]. Physical examination features might include peripheral embolic findings, atrial fibrillation, and signs of vascular disease. Appropriate screening should include white blood cell count, LDH, and Urine analysis, and then, if indicated, an IV contrast CT.

0735-6757/$ – see front matter D 2005

398 Correspondence

References

  1. Manfredini R, La Cecilia O, Ughi G, Kuwornu H, Bressan S, Regoli F, et al. Renal infarction: an uncommon mimic presenting with flank pain. Am J Emerg Med 2000;18(3):325.
  2. Korzets Z, Plotkin E, Bernheim J, Zissin R. The clinical spectrum of Acute renal infarction. Isr Med Assoc J 2002;4(10):781 – 4.
  3. Domanovits H, Paulis M, Nikfardjam M, Meron G, Kurkeiyan I, Bankier AA, et al. Acute renal infarction. Clinical characteristics of 17 patients. Medicine 1999;78(6):386 – 94.
  4. Braun DR, Sawczuk IS, Axelrod SA. Idiopathic renal infarction. Urology 1995;45(1):142 – 5.
  5. Walsh K, Baum N, Hyman III H, Ball J, Velazquez S. Idiopathic segmental renal infarction. Urology 1985;26(2):164 – 6.
  6. Lumerman JH, Hom D, Eiley D, Smith AD. Heightened suspicion and rapid evaluation with CT for early diagnosis of partial renal infarction. J Endourol 1999;13(3):209 – 14.

Jessica S. Racusin MD Marc L. Pollack MD, PhD Department of Emergency Medicine

York Hospital York, PA 17405, USA

E-mail address: [email protected] doi:10.1016/j.ajem.2005.02.001

A case of spontaneous pneumoperitoneum

To the Editor,

Pneumoperitoneum, or free intra-abdominal air, usually results from perforation of a hollow viscus, requiring urgent Surgical repair. In approximately 10% of cases, however, pneumoperitoneum is not secondary to perforation. These cases of bspontaneous pneumoperitoneumQ (SPP) generally follow a more benign course and may not require surgical intervention. Recognized causes of SPP stem from thoracic, abdominal, gynecologic, and iatrogenic etiologies. Gyneco- logic causes are rare, but SPP has been reported to result from oral-genital sex, sexual intercourse, postpartum knee- to-chest exercises, and after routine pelvic examination. We describe a case of SPP secondary to water jet insufflation of the vagina from an accidental fall in a jetted bathtub.

A 49-year-old woman presented to the ED with a chief complaint of abdominal pain after a fall. She stated that the night before presentation, while getting out of the bathtub, she slipped and fell onto one of the jets receiving a rush of water and air into her perineal region. After getting out of the bathtub, she fell again, hitting her abdomen on the floor. Since that time, she has experienced worsening abdominal pain with distention and bloating. She reported normal appetite and normal bowel movements but noticed increased flatulence. She denied any nausea, vomiting, fever, or urinary symptoms.

On physical examination, the patient appeared well but slightly uncomfortable. Her vital signs included a blood pressure of 134/74 mm Hg, a pulse rate of 79 beats per

minute, a respiratory rate of 16 breaths per minute, a temperature of 37.38C, and an oxygen saturation of 99% on room air. There were no obvious signs of trauma. Her cardiac and pulmonary examinations were normal. Abdom- inal examination demonstrated a soft but distended abdomen with decreased bowel sounds. There was diffuse abdominal tenderness with no guarding or rebound tenderness. Rectal and pelvic examinations revealed no evidence of trauma including no evidence of bleeding or mucosal tears.

Laboratory testing included a white blood cell count of 7400, hematocrit of 35%, normal chemistry and liver function tests, and a negative serum pregnancy test. Urinalysis demonstrated 1+ white blood cell and 1+ red blood cell. The patient underwent computed tomography of the abdomen and pelvis with oral and intravenous contrast which demonstrated a large amount of free intraperitoneal air (Figs. 1 and 2). There was no evidence of bowel or solid organ injury or contrast extravasation.

The patient was seen by the general surgery service in the ED and admitted to the hospital for observation. An upper gastrointestinal tract study with water-soluble contrast was performed the next day demonstrating no extravasation. The patient’s symptoms gradually improved, and she had an uneventful hospital course. She was discharged home in 24 hours.

SPP has been attributed to multiple causes. Free intraperitoneal air is most frequently seen after open or laparoscopic surgery. This can be seen for up to 7 days after surgery [1]. SPP has been reported after colonoscopy, which may allow air to pass through a thinned intact bowel wall without a clinically significant perforation. Bronchoscopy,

Fig. 1 Computed tomography anteroposterior scout film.