Internal medicine - Nephrology Flashcards
INT - 10.1
The prevalence of diabetic nephropathy in Type 1 diabetes mellitus:
A) below 5%
B) 20–30%
C) 80–90%
D) it develops in all patients
ANSWER
B) 20–30%
EXPLANATION
Based on data in the literature, 20-30% of patients with Type 1 diabetes, and 40% of patients with Type 2 diabetes are found to develop diabetic nephropathy.
INT - 10.2
In diabetic patients treated with metformin, metformin should not be administered prior to any scheduled examination using contrast agent if eGFR <30 ml/min/1,73m2:
A) administration should be continued
B) administration should be suspended only on the day of the examination
C) administration should be suspended by two days prior to the examination
D) administration should be suspended by one week prior to the examination
ANSWER
C) administration should be suspended by two days prior to the examination
EXPLANATION
Type 2 diabetic patients treated with Metformin should suspend taking the medicine by two days prior to any examination that uses contrast agent. In addition to monitoring the blood glucose levels closely, if necessary, insulin therapy may be transiently applied. It is essential to control the renal function after the procedure, and Metformin therapy could be continued after 48 hours from the examination only if the GFR is above 30 ml/min/1.73 m2; as if GFR is below that value the use of Metformin is contraindicated. Addition of iodinated contrast agents intravenously could be nephrotoxic, and the deterioration of renal function may lead to the accumulation of Metformin to toxic levels thus leading to lactic acidosis. In diabetic patients with renal failure as hypoglycemic treatment the sulphanylurea class drug Gliquidone (or possibly Gliclazide), pioglitazone, certain DPP-4 inhibitors, and insulin could be administered.
INT - 10.3
The most important factor in the early diagnosis of diabetic nephropathy:
A) the appearance of hypertension
B) the appearance of microalbuminuria
C) the increase of serum creatinine level
D) the decrease of eGFR
ANSWER
B) the appearance of microalbuminuria
EXPLANATION
Stages in the development of diabetic nephropathy: I. Hyperfiltration, hypertrophy II. Glomerular tissue damage without clinical symptoms III. Incipient nephropathy (microalbuminuria) IV. Overt diabetic nephropathy V. Renal insufficiency
INT - 10.4
Diabetic nephropathy is reversible:
A) even if eGFR is reduced
B) in the stage of macroalbuminuria
C) in the stage of microalbuminuria
D) even if the serum creatinine is increased
ANSWER
C) in the stage of microalbuminuria
EXPLANATION
Stages in the development of diabetic nephropathy: I. Hyperfiltration, hypertrophy II. Glomerular tissue damage without clinical symptoms III. Incipient nephropathy (microalbuminuria) IV. Overt diabetic nephropathy V. Renal insufficiency
INT - 10.5
It is fundamental in the treatment of diabetic nephropathy to give:
A) renin–angiotensin–aldosterone system (RAAS) inhibitors
B) alpha-blockers
C) high-dose thiazide diuretics
D) direct vasodilator antihypertensives
ANSWER
A) renin–angiotensin–aldosterone system (RAAS) inhibitors
EXPLANATION
Stages in the development of diabetic nephropathy: I. Hyperfiltration, hypertrophy II. Glomerular tissue damage without clinical symptoms III. Incipient nephropathy (microalbuminuria) IV. Overt diabetic nephropathy V. Renal insufficiency
INT - 10.6
The progression of diabetic nephropathy may be accelerated by:
A) euglycaemia
B) increased protein intake
C) reduced salt intake
D) antihypertensive therapy
ANSWER
B) increased protein intake
EXPLANATION
Stages in the development of diabetic nephropathy: I. Hyperfiltration, hypertrophy II. Glomerular tissue damage without clinical symptoms III. Incipient nephropathy (microalbuminuria) IV. Overt diabetic nephropathy V. Renal insufficiency
INT - 10.7
In diabetic patients treated with metformin, metformin therapy can be continued after the contrast agent examination:
A) on the day of the examination
B) on the next day, irrespective of renal function
C) 48 hours after the examination, if GFR is below 30 ml/min/1,73m2
D) 48 hours after the examination, if GFR is above 30 ml/min/1,73m2
ANSWER
D) 48 hours after the examination, if GFR is above 30 ml/min/1,73m2
EXPLANATION
See the explanation of question 10.2.
INT - 10.8
Patients with Type 1 diabetes have to be screened for diabetic nephropathy:
A) upon establishing the diagnosis
B) approx. 5 years after the diagnosis was established
C) approx. 10-15 years after the diagnosis was established
D) approx. 20-30 years after the diagnosis was established
ANSWER
B) approx. 5 years after the diagnosis was established
EXPLANATION
See the explanation of question 10.3.
INT - 10.9
Patients with Type 2 diabetes have to be screened for diabetic nephropathy:
A) upon establishing the diagnosis
B) approx. 5 years after the diagnosis was established
C) approx. 10-15 years after the diagnosis was established
D) approx. 20-30 years after the diagnosis was established
ANSWER
A) upon establishing the diagnosis
EXPLANATION
See the explanation of question 10.3.
INT - 10.10
Diabetic nephropathy is likely to have developed in a diabetic patient with proteinuria
A) in the absence of diabetic retinopathy
B) if the patient has diabetic retinopathy but no haematuria
C) if the patient has diabetic retinopathy and haematuria
D) it is likely in all the above cases
ANSWER
B) if the patient has diabetic retinopathy but no haematuria
EXPLANATION
See the explanation of question 10.3.
INT - 10.11
Metformin is contraindicated in diabetic patients:
A) if the eGFR is below 30 ml/min
B) if the patient is obese
C) if the patient has hypertension
D) if the patient has thyroid disease
ANSWER
A) if the eGFR is below 30 ml/min
EXPLANATION
See the explanation of question 10.2.
INT - 10.12
Nephrotic syndrome is defined as:
A) significant proteinuria
B) hypalbuminaemia
C) predisposition to oedema
D) the concurrent presence of all three factors above
ANSWER
D) the concurrent presence of all three factors above
EXPLANATION
The most common causes of symmetrical lower extremity oedema include right ventricular heart failure, nephrotic syndrome, malnutrition, malabsorption, liver failure and kidney failure. Nephrotic syndrome is defined as persistent proteinuria exceeding 3.5 g protein per day leading to resultant hypoproteinaemia and oedema. Pyuria is not characteristic. Several anticoagulant factors are lost via the urine due to the excessive proteinuria, thus the risk of thromboembolism largely increases in patients with nephrotic syndrome. In case of severe nephrotic syndrome which is accompanied by significant increases of plasma fibrinogen levels, the long-term anticoagulant therapy with Syncumar should be considered. To eliminate the oedemas in patients with nephrotic syndrome, combined diuretic treatment (loop diuretic, potassium-sparing-diuretic) beside low salt diet is used. The underlying cause of nephrotic syndrome may involve primary renal disease, or secondary causes. In nephrotic syndrome, the most frequent primary causes vary with age: during childhood the minimal change disease, while in older age the membranous GN is more common. From young adulthood, focal segmental glomerulosclerosis (FSGS) and also the mesangiocapillary (membranoproliferative) GN represent other causes in the background of nephrotic syndrome. Among different forms of nephrotic syndrome, based on the type of excreted proteins, minimal change disease could be easily differentiated, as here the protein excreted in the urine is mainly albumin (i.e. selective proteinuria).
INT - 10.13
In case of the presence of glomerular type red blood cells in the urine sediment:
A) renal stone is suspected, the patient should be referred first to urology examination
B) tumour is suspected, the patient should be referred first to urology examination
C) glomerular disease is suspected, the patient should be referred first to nephrology examination
D) uroinfection is suspected, the patient should be referred first to urology examination
ANSWER
C) glomerular disease is suspected, the patient should be referred first to nephrology examination
EXPLANATION
In case of haematuria, the shape of red blood cells (RBCs) seen in the urine sediment refers to the origin of the haematuria. Because glomerular haematuria that leads to a typical misshape modification is characterized by membrane protrusions due to damage of their cell membrane. In the presence of intact RBCs with normal shape, extraglomerular causes of haematuria, such as bleeding, stone, tumour, haemophilia should be searched. Upon prolonged storage, RBCs take up spiky, mace-like, shrunken shape due to osmotic effects, which has to be distinguished from the glomerular type haematuria.
INT - 10.14
Analgesic nephropathy:
A) is an acute kidney injury caused by NSAIDs
B) is a chronic kidney disease caused by NSAIDs
C) is a glomerulonephritis caused by NSAIDs
D) is an acute kidney injury caused by steroidal anti-inflammatory drugs
ANSWER
B) is a chronic kidney disease caused by NSAIDs
EXPLANATION
The occurrence of analgesic nephropathy is especially common in countries where different pain relievers are available ‘over the counter’ without prescription. Amongst analgesics, those ones that contain phenacetine or combined formulas possess nephrotoxic effects. In analgesic nephropathy, as a consequence of chronic analgesic effect (most commonly after taking phenacetine or combined medications, less often in the case of taking regularly NSAIDs for years) predominantly papillanecrosis and chronic tubulointerstitial damage develop (urine concentrating ability decreases, macroscopic haematuria and sterile pyuria are present etc.), and calcification of the necrotic papillae is also commonly observed. In overt nephropathy, progression of kidney involvement can be attenuated by the cessation of analgesic abuse, or it could be even prevented in the case of minor changes. For the early diagnosis of analgesic nephropathy, taking detailed history from the patient seems essential, and in suspect cases renal ultrasound or CT scan examination is required. Examinations of i.v. urography and cystography are not suitable for the diagnosis of analgesic nephropathy.
INT - 10.16
Risk factors for acute kidney injury exclude:
A) old age
B) intravenous contrast agents
C) NSAIDs abuse
D) increased fluid intake
ANSWER
D) increased fluid intake
EXPLANATION
The prerenal causes are responsible in more than half of the cases for the development of acute kidney injury (especially absolute or relative hypovolaemia). In approximately 40% of cases there are renal causes in the aetiology (e.g. rapidly progressive glomerulonephritis), whereas postrenal causes (e.g. obstructed urinary flow) are only found in approximately 5% of cases. Dehydration, administration of i.v. contrast agents, drug toxicity (e.g. NSAIDs, cisplatin, aminoglycosides), elderly age, and heart failure are all predisposing factors for acute kidney injury. In differential diagnosis, different increases in the serum urea nitrogen and creatinine levels may be valuable. For example, in prerenal and postrenal kidney failure the increase of the urea nitrogen level is more pronounced that of the creatinine level. The polyuria is considered as positive prognostic sign in acute kidney injury (the kidneys compensate the decreased detoxifying ability by increasing the urine output). Lower (1005 or less) urine specific gravity is characteristic for this compensatory polyuria. In poor prognosis cases haemodialysis may be necessary permanently, although it may be also required temporarily in other cases.
INT - 10.17
In acute kidney injury, renal cause may be suspected in the case of:
A) isolated or marked increase of the serum carbamide nitrogen level
B) bladder retention
C) marked increase of the serum creatinine level in conjunction with less marked increase of the serum carbamide nitrogen level
D) decreased turgor of the skin and dry tongue
ANSWER
C) marked increase of the serum creatinine level in conjunction with less marked increase of the serum carbamide nitrogen level
EXPLANATION
The prerenal causes are responsible in more than half of the cases for the development of acute kidney injury (especially absolute or relative hypovolaemia). In approximately 40% of cases there are renal causes in the aetiology (e.g. rapidly progressive glomerulonephritis), whereas postrenal causes (e.g. obstructed urinary flow) are only found in approximately 5% of cases. Dehydration, administration of i.v. contrast agents, drug toxicity (e.g. NSAIDs, cisplatin, aminoglycosides), elderly age, and heart failure are all predisposing factors for acute kidney injury. In differential diagnosis, different increases in the serum urea nitrogen and creatinine levels may be valuable. For example, in prerenal and postrenal kidney failure the increase of the urea nitrogen level is more pronounced that of the creatinine level. The polyuria is considered as positive prognostic sign in acute kidney injury (the kidneys compensate the decreased detoxifying ability by increasing the urine output). Lower (1005 or less) urine specific gravity is characteristic for this compensatory polyuria. In poor prognosis cases haemodialysis may be necessary permanently, although it may be also required temporarily in other cases.
INT - 10.18
In the case of acute kidney injury and glomerular haematuria or the presence of RBC cylinders in the urine:
A) pre-renal causes should be searched
B) renal cause, e.g. acute glomerulonephritis is suspected
C) post-renal cause should be searched
ANSWER
B) renal cause, e.g. acute glomerulonephritis is suspected
EXPLANATION
See the explanations of questions 10.13 and 10.16.
INT - 10.19
The most common cause of acute kidney injury out of the following:
A) pre-renal causes
B) renal causes
C) post-renal causes
ANSWER
A) pre-renal causes
EXPLANATION
See the explanation of question 10.16.
INT - 10.20
The most common causes of primary nephrotic syndrome:
1) membranous glomerulonephritis
2) minimal change disease
3) focal segmental glomerulosclerosis
4) IgA nephropathy
A) answers 1., 2. and 3. are correct
B) answers 1. and 3. are correct
C) answers 2. and 4. are correct
D) only answer 4. is correct
E) all 4 answers arecorrect
ANSWER
A) answers 1., 2. and 3. are correct
EXPLANATION
See the explanation of question 10.12.
INT - 10.21
In the case of glomerular type haematuria after respiratory infection the following pathology/pathologies may be suspected:
1) minimal change disease
2) IgA nephropathy
3) membranous glomerulonephritis
4) acute, post-streptococcal glomerulonephritis
A) answers 1., 2. and 3. are correct
B) answers 1. and 3. are correct
C) answers 2. and 4. are correct
D) only answer 4. is correct
E) all 4 answers are correct
ANSWER
C) answers 2. and 4. are correct
EXPLANATION
The light microscopy analysis of IgA nephropathy most frequently indicates mesangial proliferative glomerulonephritis that features both mesangial cell and matrix proliferation. The immunohistology shows IgA and C3 deposition mainly in the mesangium. By electronmicroscopy, the mesangial immune deposits are also apparent. The disease regularly begins and later resumes with macroscopic haematuria following an upper respiratory infection. Clinically, it is characterized by mild proteinuria and haematuria of typically glomerular origin with dysmorphic RBCs (‘Mickey mouse cells’). Nephrotic syndrome may be observed in less than 5% of cases. Long-term follow-up data revealed that majority of patients have slow progression to which the onset of hypertension is contributing as well. Acute post-streptococcal glomerulonephritis is caused by the so-called nephritogenic strains of the β-haemolytic streptococci. Clinical symptoms typically manifest 10-14 days after acute tonsillitis, and 14-21 days after skin infectious disease (pyoderma). At that time, inflammatory signs or fever could not be observed. Typical laboratory findings include the increase of Antistreptolysin O titers and the decrease of complement levels in the serum. Initial symptoms may be symmetrical eyelid oedema and headache due to the development of hypertension.
INT - 10.22
If RAAS-inhibitor therapy was commenced for treating diabetic nephropathy, after the initiation, the following should be controlled:
1) serumcreatinine and eGFR
2) blood lipids
3) serum potassium level
4) RBC sedimentation rate
A) answers 1., 2. and 3. are correct
B) answers 1. and 3. are correct
C) answers 2. and 4. are correct
D) only answer 4. is correct
E) all 4 answers arecorrect
ANSWER
B) answers 1. and 3. are correct
EXPLANATION
See the explanation of question 10.3.