Nephrology Flashcards
A fifty year old man with dialysis dependent CKD (chronic kidney disease) is awaiting renal transplant. He complains of fatigue. On examination you note a heart rate of 95 beats per minute, a soft ejection systolic murmur that does not radiate and pallor. There are no other abnormal features.
What is the most likely cause of his fatigue? (A) heart failure (B) endocarditis (C) uraemia encephalopathy (D) anaemia (E) hyperkalaemia
(D) Anaemia - anaemia is extremely common in chronic kidney disease. It is often caused by iron deficiency or erythropoietin deficiency. In this case there are a few signs and symptoms of anaemia - the tachycardia, fatigue, pallor and aortic flow murmur.
A 43 year old man is admitted to hospital with pyelonephritis as a result of a ureteric stone. He is subsequently treated with IV antibiotics and endoscopic stone retrieval. He makes a good recovery clinically but after s few days his renal function begins to deteriorate and he develops AKI (Acute Kidney Injury). He is Apyrexial, his pulse rate is 67/min, Blood Pressure is 134/89mmHg. He is catheterised and his urine output is approximately 60ml/hour. A urine dip is performed which shows the following:
Protein: ++
Leukocyte: +
Nitrites: Negative
Blood: Trace.
What is the most likely cause of his AKI? (A) Ongoing urinary tract infection (B) Trimethoprim therapy (C) Bladder outlet obstruction (D) Renal hypo-perfusion (E) Gentamicin therapy
(E) Gentamicin therapy - the urine dip shows proteinuria which would only be present with an intrinsic renal AKI. Given he has been treated for pyelonephritis, treatment with gentamicin would be r most likely cause of an intrinsic renal AKI in this man. His blood pressure and heart rate do not suggest he is underperfusing his kidneys and bladder outlet obstruction is not possible if he has a urine output of 60mls an hour. Ongoing infection is also unlikely given he is apyrexial anc his nitrites are negative on the urine dip. Trimethoprim is not known to cause intrinsic renal damage.
A 65 year old man with a history of hypertension is reviewed. As part of a routine blood test to monitor his renal function whilst taking ramipril, the following blood results are received.
Na+ 140mmol/L K+ 4.8 mol/L Urea 6.2mmol/L Creatinine 102 micromol/L eGFR 68 ml/min
A urine dipstick is subsequently performed which is normal, and a renal ultrasound show normal sized kidneys with no abnormality detected. What stage of chronic kidney disease does this patient have?
(A) No CKD (B) Stage 1 CKD (C) Stage 2 CKD (D) Stage 3 CKD (E) Stage 4 CKD
(A) No CKD
CKD is only diagnosed in this situation if supporting tests such as urinalysis or renal ultrasound are abnormal. Stages 1 and 2 CKD are only diagnosed if there is supporting evidence to accompany the eGFR.
Factors which may affect the eGFR result include pregnancy, muscle mass (e.g. Body builders, amputees) and eating red meat 12 hours prior to the sample being taken.
CKD may be classified according to GFR.
Stage 1 - GFR greater than 90mls/min with evidence of renal damage on other tests (if all kidney tests (l.e. Normal U&E and no proteinuria) are normal there is no CKD).
Stage 2 - GFR 60-90mls/min with evidence of renal damage
Stage 3a - GFR 45-59 mls/min, a moderate reduction in renal function
Stage 3b - GFR 30-44 mls/min, a moderate reduction in renal function
Stage 4 - GFR 15-29 mls/min, a severe reduction in renal function
Stage 5 - End stage renal failure - GFR below 15 mls/min - dialysis or a renal transplant may be needed.
A 63 year old man attends for a GP appointment and states he has had two episodes of visible blood in his urine. One episode occurred last week and the other this morning. There was no pain and he denies any lower urinary tract symptoms. A urinalysis shows +++ blood and is negative for all other markers. What investigation should be requested?
(A) CT scan Pelvis (B) Urine culture (C) IV urogram (D) Cystoscopy (E) Urinary biomarkers
(D) Cystoscopy
The patient has had two episodes of painless frank haematuria. According to NICE guidelines he warrants an urgent referral on the cancer pathway due to his age and presentation. He is unlikely to have a UTI as his urinalysis is negative for leukocytes and nitrites and waiting for results of a urine culture should not delay referral for further investigations.
Gold standard for bladder cancer diagnosis is cystoscopy. It cannot be replaced by cytology or any other non-invasive test.
Ultrasound and CT can help to stage and appreciate the extent of disease.
Urinary biomarkers are used in clinical research studies for investigation and follow-up of bladder cancer but cannot be used as a substitute for cystoscopy.
Urgent referral (2 week wait) in all patients aged 45 and over with unexplained visible haematuria without UTI or visible haematuria that persists or recurs after successful treatment of UTI. Urgent referral in all patients aged 60 and over with unexplained non-visible haematuria and either dysuria or a raised white cell count on blood test.
A mother brings her 5 year old son into the emergency department. She mentions her son has had 2 days of swelling in his legs, scrotum and around the eyes. She continues to tell you that he is generally tired and his urine is noted to be frothy. She mentions a cough which has persisted. There is no other medical history except for eczema and asthma.
A renal biopsy shows no abnormalities on light microscopy, however on electron microscopy abnormal podocytes (fused) are seen.
What is the most likely diagnosis?
(A) Focal Segmental Glomerulosclerosis (B) Membranous nephropathy IgA disease (C) Rapidly Progressive Glomerulonephritis (RPGN) (D) Minimal Change Disease (E) IgA disease
(D) Minimal Change Disease
Generally proliferative glomerulonephritis causes nephritic syndrome whereas non-proliferative glomerulonephritis causes nephrotic syndrome.
The clue is the fused podocytes on electron microscopy which points to a non-proliferative glomerulonephritis. In particular Minimal Change disease as the patient is very young. MCD mostly affects children and is associated with periorbital/facial swelling and frothy urine. MCD is also associated with atopy and Hodgkin’s lymphoma.
The majority of cases are steroid responsive (80%) and cyclophosphamide is the next step for steroid resistant cases.
Mini(mal change) - think kids.
