9) Balkan Endemic Nephropathy. Interstitial nephrites. Flashcards
what is balkan endemic nephropathy
unique familial chronic renal disease with high prevalence in serbia , Bulgaria , romania , croatia and Herzegovina
prominent feature - long incubation period , familial clustering , unusual high incidence association with upper urothelilal cancer ( bladder cancer )
insidious onset at 5th decade of life
what are the clinical features of balkan endemic nephropathy ?
unspecific - and remain unrecognised for years
unsymptomatic period
, the patient becoming symptomatic only in advanced renal failure, when anemia is usually marked
then weakness (maybe due to anemia) , mild lumbar pain pallor of skin and a copper brownish discolouration of the palms and soles
in the early stages of the disease. If hypertension is established, it is usually mild or moderate. In patients with advanced renal failure, blood pressure is frequently increased as a consequence of salt and water excess
Polyuria and nocturia are features of a decreased concentrating capacity of kidneys due to the marked tubulointerstitial damage and progressive renal impairment
Uric acid, urate, and some other crystal formation is frequent
urinary tract infection
what is the diagnosis of balkan endemic nephropathy ?
Macroscopic hematuria usually reflects the presence of a urinary tract tumor.
there are no pathogenic diagnostic features - set of epidemiological , clinical , biochemical data with the pattern of pathological injury in the absences of any other renal disease = highly suggestive
lab
anemia is associated with significant loss of renal function and indication for CKD
Normo- or hypochromic normocytic anemia
intermittent tubular proteinurea maybe found early It seems that the major site of injury in BEN lies in the nephron, predominantly affecting the proximal tubule
it later becomes permanent in advanced renal failure being around 1 g/L or less
Low molecular proteinuria is a hallmark of BEN and is usually accompanied by enzymuria
early stages - sparse urinary sediment
urine concentration capacity problems preceded the decline of GFR
measuring the maximal urinary specific gravity and creatinine clearance in BEN patients has shown that the concentration capability of the kidney and the glomerular filtration rate decrease slowly and progressively over the years
ultrasound
= a variable decrease in kidney size
extreme kidney atrophy - criterion for endemic nephropathy
in BEN patients it is found that the dimension of the kidney dependent on the parental status and age of the offspring = in offspring of mother with BEN = kidney cortex thickness = hotter
with increased excretion of albumin and total protein
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shares histological similarity with tubulointerstitial kidney disease
consistent renal histological findings characterizing BEN are :
extensive hypercelllar interstitial fibrosis
associated with tubular atrophy involving medullary rays , where it decreases typical from outer medullary to inner cortex
periglomerular fibrosis
focal segmental glomeruli sclerosis
vascular - arteriolar hyalinosis
intimal fibrous hyperplasia
multifocal thickening and splitting of peritubular capillary basement membrane detected by EM
what is the cause of balkan endemic nephropathy ?
unclear but strong correlation to chronic poisoning with Aristolochic acids
endogenous = genetic predisposition
wat is the treatment for balkan endemic nephropthy ?
Dialysis or kidney transplantation may be needed
what are the characteristics of acute interstitial nephritis / tubulointerstitial disease ?
70 percent are drug induced
transient renal function disorder
inflammation of the renal interstitial
edema in the renal interstitial
what is the etiology of acute interstitial nephritis ?
allergic interstitial nephritis to drugs
analgesics - Saids
diuretics
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crystal induced interstitial nephritis
E.g, acyclovir, indinavir, ciprofloxacin, methotrexate
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infectious - bacteria , virus or fungi
autoimmune disease such as SLE , sjoren
neoplasia - leukemia , lymphoma
acute allograft rejection
what are the pathophysiology of acute interstitial nephritis ?
Allergic interstitial nephritis
Drugs, particularly antibiotics and NSAIDs, act as haptens, inducing a hypersensitivity reaction.
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Crystal-induced acute kidney injury
Drugs with low urine solubility precipitate within the renal tubules→ tubular obstruction & toxicity to tubules
clinical features of acute interstitial nephritis ?
Allergic interstitial nephritis Painless hematuria Flank pain Faint, diffuse maculopapular rash fever arthralgia
analgesia involved
- headache
- posterior back ache of kidneys
- vomitting
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Crystal-induced acute kidney injury
Patients are usually asymptomatic
Renal colic
what is the diagnosis of acute analgesic interstitial nephritis ?
Histology: diffuse interstitial inflammatory infiltrate (T lymphocytes, monocytes)
Allergic interstitial nephritis
after 2/3 days taking drugs
proteinurea less 1g/day
hematurea
high relative weight of urine
eosinophilia , eosinophilurea
sterile pyuria
anemia
urea in blood increased
creatinine in blood increased
oliguria
Crystals on brightfield microscopy
what is the treatmnet for acute interstitial nephritis ?
drug induced
- stop taking the drugs immediately
- calcium gluconium ampule
- vit c ampute
- corticosteroids
what is the etiology of chronic tubulointerstitial nephritis ?
Analgesic nephropathy
NSAIDs and acetaminophen
Formerly associated with phenacetin
Myeloma kidney (myeloma cast nephropathy)
what is pathophysiology of chronic analgesic nephropathy ?
arises from the result of daily use of analgesics
Inhibition of prostacyclin synthesis → the decrease synthesis of prostaglandins in kidneys lead to vasoconstriction
of the medullary blood vessels → papillary ischemia and papillary necrosis
what are the risk factors in developing chronic analgesic nephropathy ?
older than 60
diabetes
heart failure
sepsis
what is the diagnosis of chronic analgesic nephropathy ?
↑ BUN and creatinine Urinalysis Tubular proteinuria (usually < 2 g/24 h) Hematuria: tubulointerstitial diseases show no RBC casts or acanthocytes (in contrast to glomerulonephritis) Sterile pyuria WBC casts
histology - kidney biopsy is the only conclusive means of diagnosing tubulointerstitial nephritis although a biopsy is rarely done except when any other causes cannot be found
tubular atrophy and interstitial fibrosis
atrophic tubules may contain pas stain positive hyaline casts
other tubules may be very small containing no lumen representing a endocrine gland acini - endocrine type atrophy
patchy non specific interstitial inflammation
GLOMERULI ARE USUALLY SPARED
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sometimes papillary necrosis
Intravenous urography: test of choice for renal papillary necrosis; findings include:
Irregular papillae
Ring shadows - Contrast material extending into the space around a desquamated papilla
Filling defects in the renal pelvis
Small contrast-containing cavities in the papillary regions
