Presenter Status

Resident/Psychology Intern

Abstract Type

Case report

Primary Mentor

Kathryn Kyler, MD

Start Date

6-5-2022 11:30 AM

End Date

6-5-2022 1:30 PM

Presentation Type

Poster Presentation

Description

Background: Wilm’s Tumor (WT) is the most common renal malignancy of childhood. The initial presentation of WT may mimic infection or other malignancies with nonspecific symptoms including fever, abdominal/flank pain, or hematuria. This poses a diagnostic challenge for providers, particularly when both infection and malignancy are observed. We describe a case of WT with spontaneous necrosis initially obscured by overlying Clostridium perfringens infection, making diagnosis of the cancer difficult.

Case Description: A previously healthy 5-year-old girl presented to the emergency department with a two-day history of left flank pain and fevers. In the emergency department, she was tachycardic (130 bpm), hypertensive (116/75), and febrile (101.7F). Her abdomen was soft but distended with left-sided and flank tenderness. Initial laboratory testing revealed elevated CRP (70mg/dL) and leukocytosis (22.56 x 109 /L). Urinalysis showed 5-10 WBCs and no leukocyte esterase, blood, or nitrites. A CT abdomen/pelvis with contrast demonstrated a mass-like structure in the left upper quadrant, surrounding and splaying the left adrenal gland with inferior displacement of the left kidney. The patient was hospitalized for evaluation of her abdominal mass and management of possible sepsis with empiric ceftriaxone. Additional laboratory studies were obtained including urine cultures, plasma normetanephrine and metanephrine levels, as well as Vanillylmandelic Acid (VMA) and Homovanillic acid (HVA) levels to evaluate for catecholamine-secreting tumors such as pheochromocytoma or neuroblastoma. All were within normal limits. Her symptoms, leukocytosis and CRP gradually improved with ceftriaxone and resolution of fevers after 5 days. Given the ambiguous clinical picture favoring infectious versus oncologic diagnoses, surgical biopsy was performed. Pathology demonstrated a phlegmonous appearance of the left kidney and fibrovascular proliferation with edema/inflammation and no evidence of malignancy. Tissue cultures were positive for Clostridium perfringens. At hospital discharge, the patient transitioned to a 10-week course of cefixime for C. perfringens kidney infection with outpatient follow-up scheduled in the Infectious Disease clinic. A repeat CT abdomen/pelvis obtained 4 weeks after discharge demonstrated decreased size of the renal mass, and continued monitoring was recommended. Subsequent ultrasounds showed minimal improvement, therefore a second renal biopsy was obtained 13 weeks after discharge. The biopsy identified monomorphic small cells in varying stages of cell death with positive WT1 protein, consistent with a diagnosis of WT.

Conclusions/Discussion We present a case of WT with spontaneous necrosis and concomitant C. perfringens infection. WT may mimic other pediatric renal pathologies, such as renal hemorrhage, abscess, or other renal malignancies. While our patient’s presentation was suspicious for WT, her initial biopsy did not identify malignancy, delaying oncology referral and treatment. When our patient’s abdominal mass failed to resolve with appropriate antibiotics, further imaging and biopsy results revealed the ultimate diagnosis of WT, which had been obscured by the presence of secondary bacterial infection and significant necrosis. This case underscores the importance of avoiding confirmation bias in the setting of ambiguous clinical presentations of abdominal masses, particularly with atypical imaging or laboratory findings.

Share

COinS
 
May 6th, 11:30 AM May 6th, 1:30 PM

Wilms Tumor presenting with spontaneous necrosis and Clostridium perfringens co-infection

Background: Wilm’s Tumor (WT) is the most common renal malignancy of childhood. The initial presentation of WT may mimic infection or other malignancies with nonspecific symptoms including fever, abdominal/flank pain, or hematuria. This poses a diagnostic challenge for providers, particularly when both infection and malignancy are observed. We describe a case of WT with spontaneous necrosis initially obscured by overlying Clostridium perfringens infection, making diagnosis of the cancer difficult.

Case Description: A previously healthy 5-year-old girl presented to the emergency department with a two-day history of left flank pain and fevers. In the emergency department, she was tachycardic (130 bpm), hypertensive (116/75), and febrile (101.7F). Her abdomen was soft but distended with left-sided and flank tenderness. Initial laboratory testing revealed elevated CRP (70mg/dL) and leukocytosis (22.56 x 109 /L). Urinalysis showed 5-10 WBCs and no leukocyte esterase, blood, or nitrites. A CT abdomen/pelvis with contrast demonstrated a mass-like structure in the left upper quadrant, surrounding and splaying the left adrenal gland with inferior displacement of the left kidney. The patient was hospitalized for evaluation of her abdominal mass and management of possible sepsis with empiric ceftriaxone. Additional laboratory studies were obtained including urine cultures, plasma normetanephrine and metanephrine levels, as well as Vanillylmandelic Acid (VMA) and Homovanillic acid (HVA) levels to evaluate for catecholamine-secreting tumors such as pheochromocytoma or neuroblastoma. All were within normal limits. Her symptoms, leukocytosis and CRP gradually improved with ceftriaxone and resolution of fevers after 5 days. Given the ambiguous clinical picture favoring infectious versus oncologic diagnoses, surgical biopsy was performed. Pathology demonstrated a phlegmonous appearance of the left kidney and fibrovascular proliferation with edema/inflammation and no evidence of malignancy. Tissue cultures were positive for Clostridium perfringens. At hospital discharge, the patient transitioned to a 10-week course of cefixime for C. perfringens kidney infection with outpatient follow-up scheduled in the Infectious Disease clinic. A repeat CT abdomen/pelvis obtained 4 weeks after discharge demonstrated decreased size of the renal mass, and continued monitoring was recommended. Subsequent ultrasounds showed minimal improvement, therefore a second renal biopsy was obtained 13 weeks after discharge. The biopsy identified monomorphic small cells in varying stages of cell death with positive WT1 protein, consistent with a diagnosis of WT.

Conclusions/Discussion We present a case of WT with spontaneous necrosis and concomitant C. perfringens infection. WT may mimic other pediatric renal pathologies, such as renal hemorrhage, abscess, or other renal malignancies. While our patient’s presentation was suspicious for WT, her initial biopsy did not identify malignancy, delaying oncology referral and treatment. When our patient’s abdominal mass failed to resolve with appropriate antibiotics, further imaging and biopsy results revealed the ultimate diagnosis of WT, which had been obscured by the presence of secondary bacterial infection and significant necrosis. This case underscores the importance of avoiding confirmation bias in the setting of ambiguous clinical presentations of abdominal masses, particularly with atypical imaging or laboratory findings.

 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.