EMPHYSEMATOUS PYELONEPHRITIS - Health Sciences

Pictorial Commentary Emphysematous Pyelonephritis 

PICTORIAL COMMENTARY 

EMPHYSEMATOUS PYELONEPHRITIS 

Contributed by C Anand MD and RP Swaminathan, MD 

Department of Medicine, Jawaharlal Institute of Postgraduate Medical Education and Research 

(JIPMER), Dhanvantari Nagar PO, Pondicherry – 605006 

Address for correspondence: RP Swaminathan, Professor of Medicine, Department of Medicine, JIPMER, 

Dhanvantari Nagar PO, Pondicherry – 605006. 

(a) (b) 

(a) CT scout view of abdomen - anteroposterior 

projection: arrow points at the gas shadows in 

the region of left kidney 

(b) Non contrast CT abdomen: arrow points at 

the subcapsular gas collection in left kidney and 

arrowhead points at the gas in the calyces of left 

kidney 

Health Sciences 2012;1(2):JS006 1 An Open Access Peer Reviewed E-Journal


A 40yr old male patient, a known patient with 

type 2 diabetes and poorly controlled blood 

glucose levels presented with intermittent high 

grade fever, left sided flank pain, loss of appetite, 

decreased urine output and edema of one week 

duration. He had dysuria and hematuria as well. 

He was a diabetic for 3 years, was on oral 

hypoglycemics and had undergone operation for 

diabetic foot in the past. He had no history of 

either renal stone disease or tuberculosis in the 

past. 

Examination revealed pallor, bilateral pitting 

pedal edema and left renal angle tenderness. He 

was hemodynamically stable. Cardiovascular, 

respiratory and central nervous systems were 

normal on examination. His blood glucose at 

presentation was 320mg/dL; he had no evidence 

of diabetic ketoacidosis. 

A diagnosis of left side pyelonephritis was 

suspected and an ultrasound of kidneys, ureter 

and bladder (KUB) was done, which revealed 

gas in the left kidney and pelvis. The diagnosis 

of emphysematous pyelonephritis was 

considered and a non contrast CT of KUB was 

performed for confirmation of diagnosis and 

staging of the disease. CT of KUB revealed gas 

in the subcapsular space, parenchyma and the 

collecting system of left kidney. The diagnosis 

was – class IIIa emphysematous pyelonephritis 

of the left Kidney. Right kidney was normal. 

There was no evidence of any urinary calculi or 

obstruction. 

He was treated with intravenous antibiotics – 

ceftriaxone and ciprofloxacin empirically along 

with insulin. Antibiotics were changed to 

meropenam and amikacin based on urine 

culture which grew E.Coli. Patient became 

afebrile within 48 hrs of initiation of 

meropenam and amikacin. Patient improved 

symptomatically and required no surgical 

intervention. Renal function did not recover 

completely. This was attributed to the presence 

of underlying diabetic nephropathy. Patient was 

discharged in euglycemic state with stable renal 

functions after 4 weeks of antibiotic course, 

which included 2 weeks of 

Amikacin/Meropenam. 

CLINICAL PEARLS 

The above case provides several insights to a 

potentially life threatening infection – 

emphysematous pyelonephritis 

• Diabetes predisposes patients to severe 

infections of the urinary tract. The 

upper urinary tract may be involved in 

up to 80% of the patients. 1 

• Emphysematous pyelonephritis (EPN) 

can occur in insulin dependent and 

non- insulin dependent patients even in 

the absence of ureteric obstruction. 

• EPN may present with vague clinical 

symptoms such as fever, abdominal 

pain, nausea and vomiting with sudden 

clinical deterioration. 

• Renal angle tenderness is the most 

common clinical finding and pyuria is 

present in almost all cases. 2 

• Most patients with EPN have a 

deranged renal function at 

presentation. 3, 4 



• CT KUB is the definitive investigation 

for establishing the diagnosis. 

The commonly followed classification of EPN 

based on CT was given by Huang and Tseng. 2 

resuscitation, antibiotics and control of 

blood sugars. 

• Obstruction of the urinary tract has 

been reported in 29% of the individuals 

with emphysematous pyelonephritis. 6 

CLASS 

I 

CT FINDING 

Gas in collecting system only 

• Percutaneous nephrostomy or ureteric 

stent may be needed in a patient with 

ureteric obstruction. 

II Parenchymal gas only 

IIIa Extension of gas into 

perinephric space 

IIIb 

IV 

Extension of gas into pararenal 

space 

EPN in solitary kidney, or 

bilateral disease 

The classification serves as a useful guide for 

therapy and prognosis. 

• Nephrectomy is reserved for patients 

who are unresponsive to medical 

treatment, and fulfill one or more of the 

following criteria: possession of a 

nonfunctioning kidney, presentation of 

gross renal parenchymal destruction, 

display of a class IIIa or IIIb gas pattern, 

and existence of two or more risk 

factors. 

• Thrombocytopenia, acute renal failure, 

disturbance of consciousness and shock 

are factors which predict a poor 

outcome 2 . Other factors are bilateral 

emphysematous pyelonephritis and 

renal parenchymal necrosis on imaging 

with either no fluid content or a 

streaky/mottled gas pattern. 

• Commonest urinary pathogen causing 

EPN are E.coli and Klebsiella 

pneumonia. 4, 5 

• Initial management of EPN involves a 

three pronged approach with involves 

Management algorithm for a patient 

presenting with EPN is given below: 7 

DIABETIC PATIENT WITH FEVER, 

RENAL ANGLE PAIN AND PYURIA 

ANTIBIOTICS 



PCN OR STENT 

HYDRONEPHROSIS 

KUB XRAY* 

STONE 

NORMAL 

USG KUB 

PCD OR STENT 

GAS 

GAS 

CT 

NEPHRECTOMY OR PCD 

CHRONIC RENAL FAILURE 

PARENCHYMAL GAS 

NORMAL RENAL FUNCTION; HUANG 

AND TSENG CLASS III, FIT 

NEPHRECTOMY 

SPECIAL GROUPS 

PCD +/- NEPHRECTOMY 

BILATERAL DISEASE 

PCD 

PCD +/- NEPHRECTOMY 

SOLITARY KIDNEY 

FAILURE TO RESPOND 

Abbreviations: PCD, percutaneous drainage; 

PCN, percutaneous nephrostomy. Asterisks 

denote alternatives for where CT is not readily 

available. 

References 

1. Forland M, Thomas V, Shelokov A. 

Urinary tract infections in patients with 

diabetes mellitus: studies on antibody 

coating of bacteria. JAMA1977; 

238:1924-6. 

2. Huang JJ and Tseng CC. 

Emphysematous pyelonephritis: 

Clinicoradiological classification, 

management, prognosis and 

pathogenesis. Arch Intern Med 

2000;160:797-805. 

3. Michaeli J, Mogle P, Perlberg S, 

Herman S and Caine M. 

Emphysematous pyelonephritis. J Urol 

1984; 131, 205–207. 

4. Shokeir AA, eL-Azab M, Mohsen T and 

el Diosly T. Emphysematous 

pyelonephritis. A 15 year experience 

with 20 cases. Urology 1997;49:343– 

346. 

5. Chen MT, et al. Percutaneous drainage 

in the treatment of emphysematous 

pyelonephritis : a 10 year experience. J 

Urol 1997; 157:1569–1573. 

6. Stein JP, et al. Bilateral emphysematous 

pyelonephritis: a case report and review 

of the literature. Urology 1996;47:129– 

134. 

7. Pontin AR and Barnes RD. Current 

management of emphysematous 

pyelonephritis. Nat Rev Urol 2009; 



6:272-279.

EMPHYSEMATOUS PYELONEPHRITIS - Health Sciences

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?