Acute Renal Failure during Pregnancy Secondary to Spontaneous Perirenal Hematoma

Abstract

A 32-year-old pregnant female presented with right flank pain, hematuria, and ARF at 25 weeks of gestation. Imaging studies demonstrated right perinephric hematoma, which compressed the inferior vena cava. ARF improved with expectant care as the hematoma gradually resolved.

Keywords:

• spontaneous perirenal hematoma
• acute renal failure
• May-Hegglin anomaly
• pregnancy

CASE PRESENTATION

A 32-year-old female was admitted to the hospital at 25 weeks and 5 days of gestation with a one-day history of right flank pain. Episodic gross hematuria had been noted for about five weeks prior. There was no previous history of flank pain or kidney stones.

She was diagnosed with May-Hegglin anomaly (MHA)[1] at age four, a trio of thrombocytopenia, giant platelets, and Dohle-like inclusion bodies in neutrophils. This disorder can be associated with minor bleeding episodes, but she never had any bleeding problems except a few episodes of minimal oozing from her gums in childhood.

The patient had known chronic kidney disease (CKD) of uncertain etiology with prior documented proteinuria and microhematuria. Her serum creatinine(Cr) had been in the range of 1.3–1.5mg/dL for the last three years. At 19 weeks of gestation, she was suspected to be developing superimposed preeclampsia because she exhibited new onset HTN, an increase in proteinuria, and elevation of the Cr to 1.7mg/dL. Ultrasound (US) of kidneys showed echogenic kidneys. CKD was presumed to be secondary to MHA, as the evaluation for the cause was negative.

When admitted this time, she was afebrile with BP of 187/78 mmHg. The abdomen was mildly tender in the right flank without any rigidity or rebound tenderness. On pelvic examination, there was no bleeding or sign of labor. Laboratory results showed WBC12.3 × 10³, hemoglobin 8.9 g/dL, platelets 25 × 10³, BUN 20 mg/dL, and creatinine 1.9 mg/dL. Urine analysis showed 300mg/dL protein and numerous RBCs. Urine culture was negative. Renal US showed no change from recent study.

Three days later, she had another episode of gross hematuria and the right flank pain intensified. Serum Cr rose to 3.4mg/dL. Repeat renal US showed a renal/perirenal mass over mid- to lower-aspect of the right kidney. CT scan revealed a large mixed density mass 7.7 × 8.2 × 7.4 cm with a component of hemorrhage in the right perirenal space.

The finding of this new renal mass was surprising because prior renal US had not shown any mass. For clarification, a MRI was done. It didn't reveal any mass but rather showed complex right perirenal hematoma. MRA showed compressed IVC and right renal vein secondary to hematoma (see Figures 1 and 2).

Figure 1. MRI shows complex right perirenal hematoma.

Figure 2. MRA of IVC shows patent IVC with area of flattening secondary to right perirenal hematoma (large arrow). The left renal vein is visualized and patent (small arrow). Compressed right renal vein secondary to right perirenal hematoma is not visualized on the MRA.

The patient had a spontaneous perirenal hemorrhage. She was closely monitored and was given periodic platelet transfusion as prophylaxis for any recurrent hemorrhage. Repeat CT scan of abdomen 10 days later showed interval reduction in size of hematoma. Correspondingly, the Cr declined to 2.2mg/dL, where it remained throughout the duration of pregnancy. She underwent caesarean section at the 29^th week of pregnancy due to fetal indications. A healthy infant was born. Two months later, her serum Cr came down to the baseline value of 1.5mg/dL and remained stable afterward.

DISCUSSION

Spontaneous perirenal hematoma (SPH) appeared to be the main factor underlying the ARF in this pregnant woman. She exhibited all features of SPH,[2] including acute flank pain, gross hematuria, worsening of hypertension, and increased proteinuria. There was little evidence to suspect any other cause for the sudden deterioration of her chronic renal insufficiency. The improvement in ARF paralleling the resolution of hematoma strengthens the argument of a cause-and-effect relationship.

The patient had clinical evidence of preeclampsia and a platelet abnormality. Both conditions can predispose to SPH.[2],[3] ARF resolved with the resolution of hematoma but serum Cr did not reach the baseline until after delivery. The two-step improvement in renal function suggested a role for both the resolution of hematoma and the cure of preeclampsia following the termination of pregnancy.

In summary, this patient with underlying CKD developed ARF due to SPH. This is the first case report of ARF secondary to spontaneous perirenal hematoma in a pregnant patient.