Skip to main content

Emphysematous pyelonephritis - Review

 DEFINITION 
Emphysematous pyelonephritis is an acute necrotizing infection characterized by gas formation.
It is characterized by the presence of gas in and around the kidney.

 ETIOLOGY 
E. coli (58%) and K. pneumoniae (21%) are the organisms most commonly isolated. Clostridium and Enterobacter spp may also be responsible, 7% each.

 RISK FACTORS 
1) Diabetes mellitus (70-90%)- usually patients with poor glucose control. High levels of glucose in the urine serve as a substrate for these bacteria and large amounts of gas are generated through natural fermentation
2) Obstruction (25-40%)- it is another common predisposing factor for emphysematous pyelonephritis.

For non-diabetics, protein fermentation is a proposed source of gas formation.

 CLINICAL FEATURES 
7% of cases may be asymptomatic.
If symptomatic, patients may complain of pneumaturia, irritative lower tract voiding symptoms, flank pain or may present in a severe septic condition with an acute abdomen and high grade fever.

 DIAGNOSIS 
1) Plain radiograph of the abdomen can help us in 80-85 % of cases.
2) CT is considered the optimal imaging technique for confirming emphysematous infection and characterizing the extent of involvement.

According to radiological findings and CT scans, emphysematous pyelonephritis can be classified as follows:
Class 1— gas confined to the collecting system
Class 2— gas confined to the renal parenchyma alone
Class 3A— perinephric extension of gas or abscess
Class 3B— extension of gas beyond the Gerota fascia
Class 4— bilateral EPN or EPN in a solitary kidney
Emphysematous pyelonephritis

 Plain abdominal radiograph showing presence of air around the left kidney

Emphysematous pyelonephritis
 CT scan showing left emphysematous pyelonephritis with presence of gas and parenchymal destruction
Emphysematous pyelonephritis
CT scan of a diabetic patient with emphysematous pyelonephritis due to uncontrolled diabetes and renal stones.


 MANAGEMENT 
1) Medical management includes antimicrobial therapy, bladder drainage and glycemic control.   effective.
2) Surgical intervention usually is required for only 10% of the cases. Emergency nephrectomy was traditionally considered necessary but currently, percutaneous drainage is the recommended initial approach.

 Later, elective nephrectomy may be required for some patients.


First published on: 15 April 2017

Comments

  1. Recently we came across a case of emphysematous PN - she came with flank pain and fever with rigors - - had uncontrolled DM - USG kidneys showed air around the kidney. CT KUB cnfirmed it - She was treated with IV meropenem and recovered. The post is useful and we may really come across such a pt in our pratice.

    ReplyDelete

Post a Comment

Popular posts from this blog

Hypokalemia - Potassium replacement calculation

 DEFINITION  Hypokalemia is defined as a serum potassium level of less than 3.5 mmol/L. Normal level= 3.5-5.5 mmol/L. It is encountered in >20% of patients. Patients are usually asymptomatic but severe arrhythmias and rhabdomyolysis can occur. Non-specific complaints include easy fatiguability and skeletal muscle weakness. The preferred method of replacement is via the oral route but at times this is not possible. The article below will give you an idea about how to calculate the amount of KCl to be given I.V. 1) Potassium deficit in mmol is calculated as given below: K deficit  (mmol) = (K normal lower limit  - K measured ) x kg body weight x 0.4 2) Daily potassium requirement is around 1 mmol/Kg body weight. 3) 13.4 mmol of potassium found in 1 g KCl . ( molecular weight KCl = 39.1 + 35.5 = 74.6) Suppose we get an asymptomatic patient of  70 Kg with a serum potassium level of 3.0 mmol/L and he is on nil by mouth but having an adequate diuresis, w

The plantar reflex - Babinski's sign

The plantar response is an important test to identify an upper motor neuron lesion.  PROCEDURE  To elicit it, the muscles of the lower limbs must be relaxed. The outer edge of the sole of the foot is stimulated by firmly scratching a blunt object like a key or a stick along it from the heel towards the little toe. This is what  Joseph Babinski did in the year 1896. He described the 'great toe sign' that year and then in 1903 the 'toe abduction or fan sign'. Nowadays, a final medial movement across the sole of the metatarsus is also done. i.e. we start at the heel to the little toe and finally arcing to the big toe. The final arcing movement is absent in the original Babinski plantar response test. Babinski sign refers to a combination of 'the great toe sign' and the 'fan sign'.  SIGNIFICANCE  The normal response is plantar flexion of the toes (down going) and they are drawn together. More precisely, there is flexion of the big toe and addu

Apgar scoring - table, mnemonic

 INTRODUCTION  The  Apgar score  was devised in 1952 by Dr Virginia Apgar (anesthesiologist) as a simple and repeatable method to quickly and summarily assess the health of newborn children immediately after birth.  This helps to identify those requiring resuscitation and can also be used to predict survival in the neonatal period.   MNEMONIC  A mnemonic for learning purposes includes: A - Appearance (skin colour) P - Pulse (heart rate) G - Grimace (reflex irritability) A - Activity (muscle tone) R - Respiration  Another mnemonic is also useful:  How -   Heart rate Ready - Respiration Is -        Irritability This -    Tone Child -   Colour Apgar scoring is divided into 1 and 5-min scores.  1-MIN SCORE    Sixty seconds after complete birth, the five parameters specified in the table above must be evaluated and scored. A total score of 10 indicates that the baby is in the best possible condition. A score between 0-3 me

Differences between hyperemia and congestion

Hyperemia and congestion both indicate a local increased volume of blood in a particular tissue. Hyperemia is an active process that result from augmented blood flow due to arteriolar dilation (e.g. at sites of inflammation or in skeletal muscle during exercise). The affected tissue is redder than normal because of engorgement with oxygenated blood. Congestion, on the other hand, is a passive process resulting from impaired venous return out of a tissue. It may occur due to systemic causes like cardiac failure or a local cause like isolated venous obstruction. The tissue is cyanosed because the worsening congestion leads to accumulation of deoxygenated hemoglobin in the affected tissues. 

Edema - Definition, pathophysiology, causes, clinical features

 DEFINITION  Edema is an abnormal presence of excessive fluid in the interstitial space.  PATHOPHYSIOLOGY  The movement of water and low molecular weight solutes such as salts between the intravascular and interstitial spaces is controlled primarily by the opposing effect of vascular hydrostatic pressure and plasma colloid osmotic pressure. Normally the outflow of fluid from the arteriolar end of the microcirculation into the interstitium is nearly balanced by inflow at the venular end. A small residual amount of fluid may be left in the interstitium and is drained by the lymphatic vessels, ultimately returning to the bloodstream via the thoracic duct. Either increased capillary pressure, diminished colloid osmotic pressure or inadequate lymphatic drainage can result in an abnormally increased interstitial fluid i.e. edema. An abnormal increase in interstitial fluid within tissues is called edema, while fluid collections in the different body cavities are variously