Exam Questions Flashcards
Which glomerulonephritis is most likely to rapidly recur in a renal allograft?
FSGS
Pathophysiology of vascular calcification in CKD
- Vascular calcification in CKD involves major disturbance of the calcium phosphate homeostasis and reductions in serum fetuin and pyrophosphate levels.
- In terms of pathobiology, vascular smooth muscle cell (VSMC) apoptosis and osteochondrogenic metaplasia is driven by hyperphosphataemia, worsened by iatrogenic
hypoparathyroidism and low-turnover bone disease. - Whilst antecedent diabetes mellitus, hypertension, dyslipidaemia and the metabolic syndrome continue
to contribute to arteriosclerosis, HYPERPHOSPHATAEMIA, REDUCE KLOTHO AND IMPAIRED SOFT TISSUE CALCIFICATION DEFENCES are key pathophysiological
components of this condition.
Hb Aims of EPO and why
Aim Hb < 115
Not > 130 as risk of stroke, headache, high BP, VTE, vascular access thrombosis
Risk factors for developing BK virus
The risk factors associated with BKN include:
• Aggressive immunosuppressive treatment during the acute rejection, especially the usage of monoclonal antibodies such as anti-thymocyte globulin (ATG)
• Older recipient age
• Female donor
• HLA DR mismatching.
In developed countries, which one of the following bone disorders is most
frequent in patients receiving maintenance haemodialysis?
A. Osteitis fibrosa cystica
B. Adynamic bone disease
C. Osteomalacia
D. Dialysis-related amyloidosis
E. Aluminium bone disease
B. Adynamic bone disease
Adynamic bone disease (ABD) is a variety of renal osteodystrophy characterized by reduced osteblasts and osteoclasts, no accumulation of osteoid and markedly low bone turnover.
Osteitis fibrosa cystica (OFC) is a skeletal disorder caused by an overproduction of parathyroid hormone from the overactive parathyroid glands. Osteitis fibrosa cystica is the late manifestation of the hyperparathyroidism.
Features of dialysis related amyloidosis
- Dialysis-related amyloidosis (DRA) is a disorder caused by deposition of beta-2 microglobulin as amyloid deposits.
- The clearance of beta-2 microglobulin is diminished with decreasing renal function.
- DRA is relatively common in patients, especially older adults, who have been on haemodialysis for more than 5 years. Newer haemodialysis membranes, as well
as peritoneal dialysis, can facilitate a greater clearance of beta-2 microglobulin, but are insufficient to keep blood levels normal. - Renal transplantation can ameliorate the condition.
- Carpal tunnel syndrome and shoulder pain are the most common presentations of DRA.
- The bone lesions are typically cystic and seen at the end of long bones.
- The cystic lesions contain amyloid, enlarge with time and may lead to pathological fractures of carpal bones, the femur and humeral heads, fingers, acetabulum and
distal radius.
Which one of the following is NOT a risk factor for contrast-induced acute kidney injury? A. Congestive heart failure B. Metformin C. Multiple myeloma D. Non-steroidal anti-inflammatory drugs E. Sepsis
B. Metformin
Mechanism of action of mycophenolate
PURINE SYNTHESIS INHIBITOR Mycophenolate mofetil (MMF, CellCept) is a prodrug of mycophenolic acid (MPA), an inhibitor of inosine-5'-monophosphate dehydrogenase. MPA depletes guanosine nucleotides preferentially in T and B lymphocytes and inhibits their proliferation, thereby suppressing cell-mediated immune responses and antibody formation
Mycophenolate is listed as a category D drug. It
increases first-trimester pregnancy loss and congenital malformation, including cleft lip and palate, and anomalies in distal limbs and heart, and should be
discontinued.
In renal transplant patients, what combination of immunosuppressive can be given
Combination of calcineurin inhibitor, azathioprine and
prednisolone
A 54-year-old man on regular haemodialysis presents with lower back pain
and fever. You request a magnetic resonance imaging (MRI) study of the spine,
but request that gadolinium not be used during the test because of concern
about:
A. Contrast-induced nephropathy
B. Nephrogenic systemic fibrosis
C. High incidence of allergy reaction to gadolinium among patients on
haemodialysis
D. Heavy metal toxicity
E. Systemic sclerosis
B. Nephrogenic systemic fibrosis
- Nephrogenic systemic fibrosis (NSF) is seen only in patients with kidney failure and is characterised by symmetrical skin involvement with extensive waxy thickening and hardening of the extremities and torso. Can also cause fibrosis of deeper structures, eg: lungs.
- Histologically it is characterised by marked expansion and fibrosis of the dermis with CD34-positive
fibrocytes. - This condition is associated with exposure to gadolinium, which is a hyperosmolar contrast agent used primarily during magnetic resonance imaging (MRI) or
angiography (MRA) studies. Free gadolinium is highly toxic and insoluble in water and so it has to be chelated for human administration. These gadolinium chelates
are excreted almost exclusively by the kidneys. - Gadolinium should be avoided in patients with a glomerular filtration rate (GFR) of less than 30 mL/min.
- The latent period between gadolinium exposure and disease onset is usually 1–4 weeks. Skin changes and joint contractures can occur. Since the recognition
of the dangers of gadolinium in patients with impaired renal function, the incidence of NSF has dramatically declined. - In patients with significant renal impairment (GFR <30 mL/min) in whom the use of gadolinium is imperative, such as liver transplant work-up, haemodialysis
after the exposure should be considered. Gadolinium chelates have a molecular weight of 500–1000 kDa and are removed by haemodialysis. A single conventional haemodialysis will remove 75% of a dose. A second treatment will remove 93% of a dose. Minimum adequate doses of gadolinium should be used.
What is the most important risk factor for the development of post-transplant
lymphoproliferative disorder (PTLD) in solid organ transplantation?
A. Kidney transplantation as opposed to other solid organ transplants
B. Epstein–Barr virus status mismatch between recipient and donor
C. Use of the monoclonal anti-CD52 antibody, alemtuzumab
D. Use of sirolimus
E. Previous infection with cytomegalovirus (CMV)
B. Epstein–Barr virus status mismatch between recipient and donor
A 48-year-old man presents with severe right-sided loin pain radiating to the
scrotum. A computed tomography scan demonstrates a 4-mm distal ureteric
calculus. Which one of the following treatments has been shown to increase the
chances of stone passage?
A. Frusemide
B. Tamsulosin
C. Atenolol
D. Intravenous saline
E. Thiazide diuretics
B. Tamsulosin
Alpha-1-adrenergic receptor antagonists such as tamsulosin can promote the chances of stone passage. Alpha-1 receptors are located in the human ureter, especially the distal ureter, and alpha-blockers have
been demonstrated to increase expulsion rates of distal ureteral stones, decrease time to expulsion and decrease need for analgesia during stone passage. Up to
98% of small stone of less than 5 mm may pass spontaneously.
Post-transplantation lymphoproliferative disease (PTLD)
- Post-transplantation lymphoproliferative disease (PTLD) carries a high mortality
- Most cases of PTLD are induced by Epstein–Barr virus (EBV). A seronegative renal transplant recipient who receives a seropositive kidney is at high risk of developing PTLD.
Treatment:
The reduction of immunosuppression forms the cornerstone of all treatment and may be sufficient by itself, with a complete remission rate of 63% in some reports.
A 38-year-old woman presented with bilateral red eyes, which was diagnosed as anterior uveitis. This was treated with topical steroids and improved. One month later, she represented with acute deterioration of her renal function
(creatinine 250 μmol/L, reference range: 60–100 μmol/L). Moderate proteinuria
(1.5 g/24 h) and urine eosinophilia were detected. There are no significant dysmorphic red blood cells or casts in the urinary sediment. Renal ultrasound showed
both kidneys were normal in size and appearance. She had a percutaneous renal biopsy. What is the biopsy likely to show?
A. Membranous nephropathy
B. Minimal change disease
C. Tubulointerstitial nephritis
D. Focal and segmental glomerulosclerosis
E. IgA nephropathy
C. Tubulointerstitial nephritis
- The patient in the vignette has tubulointerstitial nephritis and uveitis (TINU) syndrome
- The proposed diagnostic criteria for definite TINU specifies that affected patients’ renal biopsy should be consistent with acute tubulointersitial nephritis (ATIN) and the onset of bilateral uveitis 2 months or less before or less than 12 months after ATIN.
- Most patients with TINU are adolescents and young women. Renal disease in these patients is usually self-limited but some may develop progressive renal
failure. Histocompatibility leucocyte antigen (HLA) haplotype DQA101/DQB105/ DRB1*01 may be of importance in TINU susceptibility. - ATIN in this syndrome is typically treated with prednisolone and good results have been reported.
- Topical and systemic corticosteroids have been used for uveitis with success. Recurrences of uveitis are common.
Glomerular diseases include a wide range of immune and non-immune insults
that may target and injure the podocyte. Which of these is true?
A. The degree of podocytopenia predicts the progression of diabetic kidney
disease
B. Podocyte proliferation is a feature of minimal change disease
C. Foot process effacement is seen in membranous nephropathy
D. Expression of slit diaphragm proteins are not altered in nephrotic
disorders
E. Podocytes do not undergo programmed cell death
A. The degree of podocytopenia predicts the progression of diabetic kidney
disease
