Chapter 340 Tubuloinyerstitial Diseases of The Kidney

Question 1

The acute nature of this group of disorders may be caused by aggressive inflammatory infiltrates that lead to tissue edema, tubular cell injury, and compromised tubular flow, or by frank obstruction of the tubules with casts, cellular debris, or crystals.

Answer 1

Acute TIN

Question 2

(glycosuria, phosphaturia, aminoaciduria, hypokalemia

Answer 2

Fanconi’s syndrome

Question 3

predominant pathology includes
interstitial fibrosis with patchy mononuclear cell infiltration and widespread tubular atrophy, luminal dilation, and thickening of tubular basement membranes

Answer 3

chronic TUBULOINTERSTITIAL nephritis CTIN

Question 4

accounts for no more than ~15% of cases of unexplained acute renal failure

Answer 4

Allergic interstitial nephritis

Question 5

classic presentation , namely, fever, rash, peripheral eosino- philia, and oliguric renal failure occurring after 7–10 days of treatment with methicillin or another β-lactam antibiotic, is the exception rather than the rule.

Answer 5

Allergic interstitial nephritis

Question 6

In AIN, Atypical reaction can occur most notably by ____ which fever, rash, and eosinophilia are rare, but acute renal failure with heavy proteinuria is common.

Answer 6

NSAID INDUCED AIN

Question 7

In AIN, Urinalysis reveals

Answer 7

pyuria with white blood cell casts and hematuria.

Question 8

systemic autoimmune disorder that primarily targets the exocrine glands, especially the lacrimal and salivary glands, and thus results in symptoms, such as dry eyes and mouth, that consti- tute the “sicca syndrome”

Answer 8

SJÖGREN’S SYNDROME

Question 9

is the most common renal mani- festation of Sjögren’s syndrome

Answer 9

Tubulointerstitial nephritis with a predominant lymphocytic infiltrate

Question 10

associated with distal RTA, nephrogenic diabetes insipidus, and moderate renal failure

Answer 10

SJÖGREN’S SYNDROME

Question 11

Sjögren’s syndrome Diagnosis is strongly supported by

Answer 11

positive serologic testing for anti-Ro (SS-A) and anti-La (SS-B) antibodies.

Question 12

A large proportion of patients with Sjögren’s syndrome also have

Answer 12

polyclonal hypergammaglobulinemia

Question 13

Treatment of SJS initially with glucocorticoids, although patients may require maintenance therapy with ____ to prevent relapse

Answer 13

azathioprine or mycophenolate mofetil

Question 14

is a systemic autoimmune disease of unknown etiology. It accounts for fewer than 5% of all cases of AIN, affects females three times more often than males, and has a median age of onset of 15 years.

Answer 14

TINU

Question 15

hallmark feature of TUBULOINTERSTITIAL NEPHRITIS WITH UVEITIS (TINU) in addition to a lymphocyte-predominant interstitial nephritis is

Answer 15

a painful anterior uveitis, often bilateral and accompanied by blurred vision and photophobia.

Question 16

Diagnoses is often confounded by the fact that the ocular symptoms precede or accompany the renal disease in only one-third of cases.

Answer 16

TUBULOINTERSTITIAL NEPHRITIS WITH UVEITIS (TINU)

Question 17

Additional extrarenal features include fever, anorexia, weight loss, abdominal pain, and arthralgia. The presence of such symptoms as well as elevated creatinine, sterile pyuria, mild proteinuria, features of Fanconi’s syndrome, and elevated erythrocyte sedimentation rate should raise suspicion for this disorder.

Answer 17

TINU

Question 18

TINU:
The renal and ocular manifestations generally respond well to oral glucocorticoids, although maintenance therapy with agents such as ____may be necessary to prevent relapses

Answer 18

methotrexate, azathioprine, or mycophenolate

Question 19

Some patients may present with features of AIN but follow a pro- tracted and relapsing course.

Answer 19

GRANuLOMATOuS INTERSTITIAL NEPHRITIS

Question 20

Renal biopsy in such patients reveals a more chronic inflammatory infiltrate with granulomas and multinucleated giant cells.

Answer 20

GRANuLOMATOuS INTERSTITIAL NEPHRITIS

Question 21

In GRANuLOMATOuS INTERSTITIAL NEPHRITIS
Most often, no associated disease or cause is found; however, some of these cases may have or subsequently develop the pulmonary, cutaneous, or other systemic manifestations of

Answer 21

sarcoidosis such as hypercalcemia.

Question 22

is a rare cause of granulo- matous interstitial nephritis.

Answer 22

Tuberculosis

Question 23

Autoimmune pancreatitis, sclerosing cholangitis, retroperitoneal fibrosis, and a chronic scleros- ing sialadenitis (mimicking Sjögren’s syndrome) may variably be pres- ent as well.

Answer 23

IgG4 related systemic disease

Question 24

Fibrotic lesions that form pseudotumors in the affected organs soon replace the initial inflammatory infiltrates and often lead to biopsy or excision for fear of true malignancy.

Answer 24

IgG4 related systemic disease

Question 25

Presently, infection-associated AIN is most often seen in immunocompromised patients, particularly

Answer 25

renal transplant recipients with reactivation of polyomavirus BK

Question 26

Urinalysis reveals “sheaf of wheat” sulfonamide crystals,

Answer 26

tubular obstruction that may occur in patients treated with sulfadiazine for toxoplasmosis,

Question 27

Ua reveals individual or parallel clusters of needle- shaped indinavir crystals

Answer 27

Tubular obstruction from indinavir and atazanavir for HIV

Question 28

Urinalysis showing red-green birefringement needle-shaped crystals of acyclovir.

Answer 28

Tubular obstruction from intravenous acyclovir for severe herpesvirus infections.

Question 29

A dense precipitate of birefringent uric acid crystals is found in the urine, usually in association with microscopic or gross hematuria

Answer 29

acute urate nephropathy

Question 30

is an uncommon but serious complication of oral Phospho-soda used as a laxative or for bowel preparation for colonoscopy.

Answer 30

Acute phosphate nephropathy

Question 31

commonly known as myeloma kidney—should be considered in patients who fail to recover when the precipitating factor is corrected or in any elderly patient with other- wise unexplained acute renal failure.

Answer 31

light chain cast nephropathy (LCCN)

Question 32

In this disorder, filtered monoclonal immunoglobulin light chains (Bence-Jones proteins) form intratubular aggregates with secreted Tamm-Horsfall protein in the distal tubule

Answer 32

light chain cast nephropathy (LCCN)

Question 33

Clinical clues to the diagnosis include anemia, bone pain, hypercalcemia, and an abnormally narrow anion gap due to hypoalbuminemia and hypergammaglobulinemia.

Answer 33

light chain cast nephropathy (LCCN)

Question 34

detection of increased amounts of protein in a spot urine specimen and a negative dipstick result are highly suggestive that the urine contains

Answer 34

Bence-Jones protein

Question 35

is the consequence of vesicoureteral reflux (VUR) or other urologic anomalies in early childhood

Answer 35

Reflux nephropathy

Question 36

stems from abnor- mal retrograde urine flow from the bladder into one or both ureters and kidneys because of mislocated and incompetent ureterovesical valves

Answer 36

vesicoureteral reflux (VUR)

Question 37

In VUR, result is patchy interstitial scarring and tubular atrophy. Loss of functioning nephrons leads to hypertrophy of the remnant glomeruli and eventual secondary

Answer 37

FSGS

Question 38

Renal ultrasound in adults characteristically shows asymmetric small kidneys with irregular outlines, thinned cortices, and regions of compensatory hypertrophy

Answer 38

vesicoureteral reflux (VUR)

Question 39

In VUR, Aggressive control of blood pressure with _____ is effective in reducing proteinuria and may significantly forestall further deterioration of renal function.

Answer 39

an angiotensin-con- verting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) and other agents

Question 40

In 1. _____ there is evidence of tubular injury and may be evident in childhood and early adolescence in the form of 2.____ due to decreased concentrating ability or 3. ______ years before there is significant nephron loss and proteinuria from secondary FSGS.

Answer 40

1. Sickle cell nephropathy
2. Polyuria
3. type IV renal tubular acidosis (RTA)

Question 41

MajOr Causes OF papILLary neCrOsIs

Answer 41

analgesic nephropathy
Sickle cell nephropathy
Diabetes with urinary tract infection
Prolonged NSAID use (rare)

Question 42

results from the long-term use of compound analgesic preparations containing phenacetin (banned in the United States since 1983), aspirin, and caffeine.

Answer 42

analgesic nephropathy

Question 43

most prudent approach in lithium associated nephropathy is to monitor lithium levels frequently and adjust dosing to avoid toxic levels

Answer 43

<1 meq/L)

Question 44

in lithium associated nephropathy, patients who develop significant proteinuria, ____ treatment should be initiated

Answer 44

ACEI or ARB

Question 45

calcineurin inhibitor (CNI) immunosuppressive agents ____ can cause both acute and chronic renal injury.

Answer 45

cyclosporine and tacrolimus

Question 46

is typically seen in solid organ (including heart-lung and liver) transplant recipients and manifests with a slow but irreversible reduction of glomeru- lar filtration rate, with mild proteinuria and arterial hypertension.

Answer 46

Chronic CNI-induced renal injury

Question 47

is a relatively common complication of calcineurin-inhibitor nephropathy and is caused, in part, by tubular resistance to aldosterone.

Answer 47

Hyperkalemia

Question 48

triad of “saturnine gout,” hypertension, and renal insufficiency attributable to proximal tubule dysfunction

Answer 48

HEAVY METAL (LEAD) NEPHROPATHY

Question 49

a form of medullary cystic kidney disease caused by mutations in uromodulin (UMOD)

Answer 49

juvenile hyperuricemic nephropathy

Question 50

Chronic hypercalcemia, as occurs in ___(5)____, can cause tubulointerstitial disease and progressive renal failure

Answer 50

primary hyperparathyroidism, sarcoidosis, multiple myeloma, vitamin D intoxication, or metastatic bone disease

Question 51

Clinically, the most striking defect is an inability to maximally concentrate the urine, due to reduced collecting duct responsiveness to arginine vasopressin and defective transport of sodium and chloride in the loop of Henle.

Answer 51

hypercalcemic nephropathy

Question 52

Analgesic nephropathy results from the long-term use of compound analgesic preparations containing:

Answer 52

1. phenacetin (banned in the United States since 1983)
2. aspirin
3. caffeine

Question 53

Two seemingly unrelated forms of CIN, Chinese herbal nephropathy and Balkan endemic nephropathy, have recently been linked by the underlying etiologic agent aristolochic acid and are now collectively termed

Answer 53

aristolochic acid nephropathy (AAN)

Question 54

Definitive diagnosis of AAN requires two of the following three features:

Answer 54

1. characteristic histology on kidney biopsy;
2. confirmation of aristolochic acid ingestion;
   and
3. detection of aristolactam-DNA adducts in kidney or urinary tract tissue.

Question 55

It has been linked to mutations in FAN1, a nuclease involved in DNA repair, which may render carriers of the mutation susceptible to environmental DNA-damaging agents.

Answer 55

Karyomegalic interstitial nephritis