Emphysematous pyelonephritis presenting as necrotizing fasciitis of the leg.
ABSTRACT We report a 50-year-old man with poorly controlled diabetes mellitus who presented with a painful, swollen right leg. He had also experienced right flank pain for 1 week prior to admission. Physical examination was notable for tenderness over the right flank. The right leg was diffusely swollen and exquisitely tender to touch, with palpable crepitance. Laboratory tests revealed leukocytosis and pyuria. Computed tomography showed a right ureteral stone with hydronephrosis and characteristic findings of emphysematous pyelonephritis. Furthermore, a right perirenal gas-forming abscess with extension to the right leg was noted. The patient was successfully treated with antibiotic therapy, aggressive control of blood sugar, percutaneous drainage of the hydronephrosis and perirenal abscess, and aggressive debridement of the leg.
Article: Clinical and radiological findings in patients with gas forming renal abscess treated conservatively.[show abstract] [hide abstract]
ABSTRACT: Emphysematous pyelonephritis in diabetics is considered a potentially lethal infection. Mortality rates of patients treated conservatively approaches 80% in some series. These patients often present with signs of sepsis or septic shock. In contrast, gas forming renal abscess is rare, with patients presenting entirely differently from those with emphysematous pyelonephritis. To our knowledge this process has been previously described only in isolated case reports. We describe a series of 5 patients with this distinct process. We reviewed the clinical and radiological features of 5 patients with gas forming renal abscesses. Each patient presented with diabetes mellitus with initial blood glucose ranging from 313 to 552 mg./dl., fever (average 101F), flank or abdominal pain and pyuria. No patient had evidence of septic shock at hospitalization. Escherichia coli was the documented organism in each case. Mild renal insufficiency was noted in most patients based on serum creatinine. Radiological evaluation revealed gas filled pockets within the renal parenchyma, which were most effectively shown by computerized tomography (CT) of the abdomen. There was no radiological evidence of pus. Percutaneous drainage of an abscess in 1 case did not produce any purulent material or alter the clinical course. Each patient responded to correction of the underlying metabolic abnormalities with intravenous antibiotics (average 23 days) followed by prolonged oral antibiotic therapy (average 9 weeks). In contrast to the management of emphysematous pyelonephritis, surgical or percutaneous drainage was not necessary. Serial CT revealed complete resolution of gas in the parenchyma within 6 months in patients with long-term followup. Of note, gas was persistent on CT months after infection had clinically resolved. We describe a unique entity within the spectrum of pyelonephritis. The clinical appearance of gas forming abscesses within the renal parenchyma without liquefaction in diabetic patients was remarkably benign compared to the radiographic appearance of the disease process. Conservative management with intravenous and oral antibiotics was successful in each patient, avoiding the need for invasive intervention.The Journal of Urology 11/1999; 162(4):1273-6. · 3.75 Impact Factor
Article: Treatment of emphysematous pyelonephritis with broad-spectrum antibacterials and percutaneous renal drainage: an analysis of 10 patients.[show abstract] [hide abstract]
ABSTRACT: This retrospective study was designed to determine the efficacy of broad-spectrum antibacterials combined with percutaneous renal drainage in the treatment of emphysematous pyelonephritis (EPN). From July 1992 to September 2002, 10 patients (nine females and one male) with EPN were managed at our institution. All patients had diabetes and presented with fever and chills, flank pain or tenderness, vomiting, and altered consciousness. The diagnosis of EPN was confirmed by the presence of intraparenchymal and/or perinephric gas in imaging studies (kidney-ureter-bladder film, sonogram, and/or computed tomography scan). Broad-spectrum antibacterial therapy, combined with percutaneous renal drainage, was started in all patients. Follow-up studies consisted of computed tomography scan and technetium-labeled diethylenetriaminepentaacetic acid (DTPA) radioisotope renography. The outcome was good in all patients. Three patients underwent delayed nephrectomy due to non-functioning of the involved kidney. The DTPA radioisotope renography results (glomerular filtration rate of the diseased kidney/ contralateral healthy kidney) were 0/57 mL/min, 2.7/68.1 mL/min and 3.7/63.9 mL/min. Combined broad-spectrum antibacterial therapy and percutaneous renal drainage is a safe and effective treatment for EPN, especially in high-risk patients for whom nephrectomy under general anesthesia is not feasible.Journal of the Chinese Medical Association 02/2005; 68(1):29-32. · 0.79 Impact Factor
[show abstract] [hide abstract]
ABSTRACT: We identified and quantified prognostic factors for emphysematous pyelonephritis. The clinical information, laboratory data and radiological findings from 38 patients with emphysematous pyelonephritis were retrospectively analyzed. There were no significant differences between the nonsurvivor and survivor groups with respect to age, gender, diabetes mellitus history, presence of bacteremia, identity of infecting organisms, blood glucose level, leukocyte count, urinary white blood count, presence or absence of urinary tract obstruction or urolithiasis, and modes of treatment. There were significant differences between the nonsurvivor and survivor groups, however, with respect to platelet count (84,300 +/- 119,500 versus 220,400 +/- 161,800/mm.3, p = 0.001), serum creatinine level (3.61 +/- 1.25 versus 2.19 +/- 1.32 mg./dl., p = 0.003) and urinary red blood counts (56.47 +/- 41.86 versus 27.65 +/- 36.14, p = 0.028). Patients with radiological type I emphysematous pyelonephritis were significantly more likely to die than those with type II (69 versus 18%, p = 0.002). Serum creatinine level is the most reliable predictor of outcome in patients with emphysematous pyelonephritis. By calculating likelihood ratios, patients with creatinine levels greater than 1.4 mg./dl. and platelet counts 60,000/mm.3 or less were at high risk. The posttest probability of death increased from 69 and 18% to 92 and 53% for type I and II emphysematous pyelonephritis, respectively. Patients with creatinine levels 1.4 mg./dl. or less and platelet counts greater than 60,000/mm.3 were at much lower risk. Posttest mortality risk in these patients dropped from 69 and 18% to 27 and 4% for type I and II emphysematous pyelonephritis, respectively.The Journal of Urology 03/1998; 159(2):369-73. · 3.75 Impact Factor
Emphysematous pyelonephritis is an uncommon and
life-threatening infection of the kidney. The disease
usually occurs in patients with diabetes mellitus, with
or without obstructive uropathy, and is characterized
by gas accumulation in the renal parenchyma, collect-
ing system, or perirenal tissue. Clinical symptoms and
signs are often similar to those of uncomplicated pyelo-
nephritis. Delay in diagnosis is usually due to nonspe-
cific manifestations, such as fever, flank pain, nausea,
and vomiting, and results in high mortality rates. We
report an unusual case of emphysematous pyelonephri-
tis presenting as necrotizing fasciitis of the ipsilateral
leg. Based on thorough history-taking and detailed
physical examination, accompanied by essential imag-
ing studies, we were able to establish an early diagnosis
and plan appropriate management, which resulted in
a good outcome.
A 50-year-old man with diabetes mellitus presented
to the emergency department with a painful, swollen
right leg. The pain and swelling began 3 days before
presentation, worsening until he was unable to walk.
Furthermore, he had experienced right flank pain for
1 week before the beginning of the right leg pain. On
physical examination, his body temperature was 38.5°C
and he had tenderness over the right flank. The right
leg was diffusely swollen and exquisitely tender to
touch, with palpable crepitance.
Complete blood count on admission showed a
white blood cell count of 19,200/μL, hemoglobin of
12.4g/dL, and platelet count of 250,000/μL. Blood
chemistries showed urea nitrogen 19.1mg/dL, crea-
tinine 1.1mg/dL, glucose 418mg/dL, and HbA1c
15.3%. Urinalysis was remarkable for 3+ occult blood,
with numerous white blood cells per high-power field
in the urinary sediments.
Computed tomography showed a right ureteral
stone with hydronephrosis and gas bubbles in the renal
parenchyma and collecting system (Figure 1). A gas-
forming abscess below the right kidney was also noted.
The presence of gas in the right lateral abdominal wall
suggested necrotizing fasciitis and an extension of the
inflammatory process from the retroperitoneal abscess.
Moreover, the necrotizing fasciitis further extended
to the right leg (Figure 2).
J Chin Med Assoc • March 2009 • Vol 72 • No 3
© 2009 Elsevier. All rights reserved.
Emphysematous Pyelonephritis Presenting as
Necrotizing Fasciitis of the Leg
Yu-Xiong Ye, Yao-Ko Wen*
Department of Internal Medicine, Changhua Christian Hospital, Changhua, Taiwan, R.O.C.
We report a 50-year-old man with poorly controlled diabetes mellitus who presented with a painful, swollen right leg. He had
also experienced right flank pain for 1 week prior to admission. Physical examination was notable for tenderness over
the right flank. The right leg was diffusely swollen and exquisitely tender to touch, with palpable crepitance. Laboratory
tests revealed leukocytosis and pyuria. Computed tomography showed a right ureteral stone with hydronephrosis and
characteristic findings of emphysematous pyelonephritis. Furthermore, a right perirenal gas-forming abscess with extension
to the right leg was noted. The patient was successfully treated with antibiotic therapy, aggressive control of blood sugar,
percutaneous drainage of the hydronephrosis and perirenal abscess, and aggressive debridement of the leg. [J Chin Med
Key Words: emphysematous pyelonephritis, necrotizing fasciitis
*Correspondence to: Dr Yao-Ko Wen, Division of Nephrology, Department of Medicine, Changhua Christian
Hospital, 135, Nanhsiao Street, Changhua 500, Taiwan, R.O.C.
● Received: May 28, 2008
● Accepted: October 17, 2008
The patient was treated with antibiotic therapy,
aggressive control of blood sugar, percutaneous drain-
age of the right hydronephrosis and perirenal abscess,
and aggressive debridement of the right leg. Urine
culture grew Escherichia coli. Culture of the perirenal
abscess grew Escherichia coli and Klebsiella oxytoca.
The result of the blood culture was negative.
Over the next 2 weeks, the patient underwent
debridement of the affected right leg twice, and per-
cutaneous nephrolithotomy was performed 1 month
after admission. The patient was discharged with the
right leg fully recovered.
Emphysematous pyelonephritis is a gas-producing,
necrotizing infection involving the renal parenchyma,
collecting system, or perirenal tissue. The mechanism
of gas formation is still unclear. Most cases occur in
uncontrolled diabetes mellitus. Other risk factors in-
clude urinary tract obstruction and urinary tract infec-
tion with gas-forming microorganisms.1Two types
of disease are recognized: type I is characterized by
extensive destruction of renal parenchyma with the
presence of mottled gas, and type II is characterized
by renal or perirenal fluid collection with loculated gas
or gas in the collecting system.2Type I emphysema-
tous pyelonephritis has a more fulminant course and
frequently requires surgical nephrectomy. For local-
ized emphysematous pyelonephritis, the success rate
of antibiotic treatment, with or without percutaneous
drainage, has improved substantially in recent years.3,4
In general, the mortality rate is higher in type I than
type II patients (69% vs. 18%).5In this case, the com-
puted tomography findings were compatible with the
description of type II emphysematous pyelonephritis.
Necrotizing fasciitis is a deep-seated infection of
subcutaneous tissue that is characterized by progressive
necrosis of the fascia and fat.6Diabetes mellitus is also
the most common predisposing factor. The disease has
a fulminant course and is associated with considerable
mortality. There may be a remarkably rapid progression
from an inapparent process to one associated with
extensive destruction of subcutaneous tissues and signs
of systemic toxicity. Early recognition and treatment
by a combination of surgical debridement, appropriate
antibiotics and optimal oxygenation of the infected
tissues are mandatory.7
Both emphysematous pyelonephritis and necrotiz-
ing fasciitis are life-threatening conditions and require
prompt aggressive medical and surgical intervention.
The combined occurrence of the 2 entities is extremely
unusual. Although necrotizing fasciitis can be caused by
a retroperitoneal infection, only 2 cases of necrotizing
fasciitis associated with emphysematous pyelonephritis
have been described previously in the literature.8–10
A pathophysiology of emphysematous pyelonephritis
extending to the adjacent subcutaneous tissues has been
proposed.9The superior and inferior lumbar triangles
are 2 sites of anatomic weakness in the abdominal wall
of the flank due to the absence of external muscular
layers. The classic sign of subcutaneous discoloration
J Chin Med Assoc • March 2009 • Vol 72 • No 3
Emphysematous pyelonephritis combined with necrotizing fasciitis
Figure 1. Computed tomography shows right hydronephrosis, gas
bubbles in the renal parenchyma and collecting system (black
arrow), and perirenal gas-forming abscess (white arrow).
Figure 2. Computed tomography, coronal view, clearly demon-
strates a right ureteral stone with hydronephrosis (black arrow)
and a gas-forming abscess below the right kidney, with extension
to the right leg (white arrow).
in the flank (Grey Turner sign) associated with acute
pancreatitis and traumatic lumbar hernia are known
to develop through these triangles.11The inferior lum-
bar triangle pathway also provides an anatomic expla-
nation for the development of necrotizing fasciitis from
the retroperitoneal infection.
In conclusion, we have presented a case of emphy-
sematous pyelonephritis complicated with necrotizing
fasciitis. Computed tomography showed characteristic
findings of emphysematous pyelonephritis and perire-
nal gas-forming abscess with extension to the ipsilateral
leg. This case not only represents a concurrence of the
2 uncommon entities but also alerts us that necrotiz-
ing fasciitis may be the presenting feature of emphyse-
matous pyelonephritis. In cases of necrotizing fasciitis
of the leg with no obvious source, a retroperitoneal
nidus of infection may be considered.
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radiological classification, management, prognosis, and patho-
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2.Wan YL, Lee TY, Bullard MJ, Tsai CC. Acute gas-producing
bacterial renal infection: correlation between imaging findings
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Best C, Terris M, Tacker J, Reese J. Clinical and radiological
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Wan YL, Lo SK, Bullard MJ, Chang PL, Lee TY. Predictors of
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J Chin Med Assoc • March 2009 • Vol 72 • No 3
Y.X. Ye, Y.K. Wen