Acute Pyelonephritis Dr Andrew Stein Consultant in Acute and Renal Medicine Clinical Commissioning Director Coventry and Rugby CCGs

Structure of Talk Definition Clinical Features Investigation Radiology Treatment Referrals Quiz

Choices Renal US/not Admit/not Renal referral/not

Definition and Diagnosis Acute pyelonephritis = ascending bacterial infection of the renal pelvis and the renal parenchyma usually presenting with fever, loin pain and bacteriuria 'Pyelonephritis': from Greek πήληξ – pyelum, meaning 'renal pelvis', νεφρός – nephros, meaning 'kidney' and -itis, meaning 'inflammation') Clinical diagnosis; no single diagnostic clinical feature or investigation

Risk Factors DM Female sex, pregnancy, intercourse Stones, bladder catheter, structural renal tract abnormality Chronic liver disease IV drug use Infective endocarditis

Classification: Complicated vs Non-Complicated UTI UTI can be 'complicated' eg acute pyelonephritis This can be the first presentation of a (treatable) structural disease of the urinary tract, or diabetes mellitus Assume all men, children, pregnant women and ill patients, have a complicated UTI; and exclude a structural cause In a man, the diagnosis of UTI should be confirmed with a MSU, as it is an important diagnosis

Structural Renal Disease Not requiring surgery Reflux nephropathy Polycystic kidney disease Duplex system Requiring surgery (Obstruction) Pelvi-ureteric junction (PUJ) obstruction Renal stones Prostatism

Organisms Escherichia coli is the commonest organism (80% community- acquired but <40% hospital-acquired) Note: other organisms (below) more associated with structural abnormalities: Proteus mirabilis 20% Staphylococcus saprophyticus 10% Klebsiella 5% Other organisms include: Streptococcus faecalis, Enterobacter, Acinetobacter, Pseudomonas aeruginosa, Serratia marascens, Candida albicans, Staphylococcus aureus Note: TB classically causes a sterile pyuria

Symptoms 75% have preceding lower urinary tract symptoms Loin pain Back pain Fever/rigors Other manifestation of severe sepsis Note: symptoms can develop over hours, or a day

Signs Pyrexia Loin tenderness Rarely, a palpable loin mass Scoliosis concave towards the affected side Of severe sepsis Of AKI (rare) Note: in prostatitis, there may be a swollen and tender prostate

Investigations (Blood and Urine) FBC, ESR, CRP U+E, LFT, Bone, Glucose (may be first presentation of DM) BC (20% +ve) Urinalysis: haematuria, proteinuria and be positive for nitrites and leucocytes; usually but not always positive MSU: pure growth of >10x5 is diagnostic (60% +ve); pyuria = > 20 WC, on microscopy

Investigations: Radiology CXR (Erect: subdiaphragmatic gas?) Renal Ultrasound (not unless male, pregnant, child, recurrent, unclear diagnosis or ill) CT (Emphysematous Pyelonephritis) CT-KUB (Stone?)

Emphysematous Pyelonephritis This is rare but life-threatening, mainly seen in patients with poorly controlled diabetes (90% have DM) Necrotising infection of the renal parenchyma and its surrounding areas that results in the presence of gas in the renal parenchyma, collecting system, or perinephric tissue. 50% mortality 70% E Coli 70% Classic finding is gas within the body of the kidney (CT) Bilateral nephrectomy may be necessary (really!)

CT abdomen

Investigation – Urinary Dipstick 3 False beliefs Protein – nil ≠ no proteinuria (= no albuminuria) Protein + ≠ UTI ‘Pos dip’ = UTI True belief Protein ≥ +++ = glomerular/interstial disease, ++ might be

Differential Diagnosis Renal colic Pelvic inflammatory disease Acute appendicitis Acute cholecystitis or diverticulitis AAA

Treatment: Antibiotics Uncomplicated: PO TRIMETHOPRIM 200 mg bd Complicated: IV GENTAMICIN 5 mg/kg od + IV CO-AMOXICLAV 1.2 g tds ± Analgesia

Treatment: Other ABG/VBG Sepsis Six ICU

Treatment: In or outpatient IV Cetotaxime 1g OD Follow-up GP Renal / not

Who to Refer to Nephrology or Urology Complicated (some) Recurrent or unclear diagnosis Pregnant woman Young (child) Male Unwell Ie, considering diagnosis structural renal disease.. if doing Renal US, refer

Complications + Indications for Surgery Renal cortical abscess (renal carbuncle) Renal corticomedullary abscess: Incision and drainage, nephrectomy Perinephric abscess: Drainage, nephrectomy Calculi-related urinary tract infection (UTI): Extracorporeal shockwave lithotripsy (ESWL) or endoscopic, percutaneous, or open surgery Renal papillary necrosis: CT guided drainage or surgical drainage with debridement Emphysematous pyelonephritis: Nephrectomy

Quiz 1.20% of patients have a positive BC 2.20% pf patients have a positive MSU 3.Urinalysis: ‘protein – nil’ = no proteinuria 4.All patients need a Renal US 5.Klebsiella is the commonest organism

Summary Acute pyelonephritis is relatively easy diagnosis 3 Big decisions.. Renal US or not Out vs Inpatient? Refer to Renal/Urology or not

Thankyou Acutemed.co.uk Renalmed.co.uk