infection, failure Flashcards
1
Q
urinary tract infection (UTI) is
A
inflammation of urinary tract
2
Q
urinary tract infection presents as
A
- suprapubic pain
- dysuria
- urinary frequency
- urgency
SYSTEMIC SYMPROMS ARE USUALLY ABSENT
3
Q
Dysuria
A
painful or difficult urination.
4
Q
UTI risk factors
A
- female (short urethra)
- sexual intercourse (honeymoon cystitis)
- idwelling catheter
- diabetes mellitus
- impaired bladder emptying
- GU malformation
- obstruction
- pregnancy
5
Q
UTI - bags
A
- E. Coli
- S. saprophyticus
- Klebsiella pneumoniae
- Serratia marcescens
- Enterococcus
- Proteus mirabilis
- Pseudomonas aeruginosa
6
Q
3 MCC of UTI (in order)
A
- E. Coli
- S. saprophyticus
- Klebsiella pneumoniae
7
Q
Serratia marcescens - special features (2)
A
- red pigment (some stains)
2. often nosocomial and drug resistance
8
Q
UTI seen in suxually active women (2 bugs in order)
A
- E. Coli
2. S. saprophyticus
9
Q
UTI - diagnostic markers
A
- leukocyte esterase –> WBC activity
- Nitrate test –> reduction of urinary nitrates by bacterial species (indicates gram (-) organism, esp E. coli)
- Urease test –> urease-producing bags (eg. Proteus, klebsiella)
10
Q
Sterile pyiria and (-) urine cultures suggest
A
urethritis by Neisseria gonorrhoeae or Chlamydia trachomatis
11
Q
Acute pyeonephritis is the
A
neutrophil infiltration of renal interstitium
12
Q
Acute pyeonephritis affects …. (location)
A
cortex with rekative sparing of glomeruli/vessels
13
Q
Acute pyeonephritis - clinical presentation
A
- fever
- flank pain (costovertebral angle tenderness)
- nausea/vomiting
- chills
14
Q
causes of Acute pyeonephritis
A
- ascending UTI (E. coli is the MC)
2. hematogenous spread to kidney
15
Q
acute pyeonephritis - lab
A
WBCs in urine +/- WBCs casts
16
Q
acute pyeonephritis - CT
A
striated parenchymal enhancement
17
Q
acute pyeonephritis - risk factors
A
- indwelling urinary catheter
- urinary tract obstruction
- vesicoulateral reflux
- DM
- pregnancy
18
Q
acute pyeonephritis - complications
A
- chronic pyeonephritis
- Renal pupillary necrosis
- perinephric abscess
- urosepsis
19
Q
Urosepsis?
A
sepsis started from UTI
20
Q
acute pyelonephritis - treatment
A
antibiotics
21
Q
chronic pyelonephritis is the result of
A
recurrent episodes of acute pyelonephritis
22
Q
chronic pyelonephritis is the result of recurrent episodes of acute pyelonephritis - typically requires
A
predisposition to infection such as vesicoulateral reflux or chronically obstruction kidney stones
23
Q
Chronic pyelonephritis - gross and histological appearance
A
coarse, asymmetric corticomedullary scarring, blunted and dilated calyx. Tubules can contain esoniphilic casts resembling thyroid tissue (thyroidization of kidney)
24
Q
Xanthogranulomatous pyelonephritis?
A
a rare condition characterized by widespread kidney damage due to granulomatous tissue containing foamy macrophages
25
Diffuse cortical necrosis - definition
Acute generalized cortical infraction of both kidneys
26
Diffuse cortical necrosis is likely due to
combination of vasospams and DIC
27
Diffuse cortical necrosis is associated with
1. obstetric catastrophes (eg, abruptio placentae)
| 2. septic shock
28
Acute kidney injury is AKA
acute renal failure
29
acute renal failure (Acute kidney injury) - definition
abrupt decline in renal function as measured by increased creatinine and increased BUN
30
acute renal failure (Acute kidney injury) - TYPES
1. Prerenal azotemia
2. Intrinsic renal failure
3. postrenal azotemia
31
Prerenal azotemia - mechanism
Due to decreased RBF (eg. hypotension) --> decreased GFR --> Na+/H20 and BUN retained by kidney in an attempt to conserve volume --> increased BUN/creatining ratio (BUN is reabsrobed, creatinine not) and decreased FENa
32
Prerenal azotemia - urine osmolairty (mOsm/Kg), urine Na+ meq/L, FENa, Serum BUN/Cr
- urine osmolairty --> more than 500
- urine Na+ less than 20
- FENa less than 1%
- Serum BUN/Cr >20
33
Intrinsic renal failure - due to
- acute tubular necrosis or ischemia/toxins
| - less commonly due to acute glomerulonephritis (RPGN, hemolytic uremic syndrome) or acute interstitial nephritis
34
Intrinsic renal failure in acute tubular necrosis - mechanism
debris obstructing tubuleand fluid backfolow across necrotic tubule --> decreased GFR --> BUN reabsorption is impaired -> low BUN/creatinine ratio
35
acute tubular necrosis - casts?
epithelial/granular casts
36
intrinsic failure - urine osmolairty (mOsm/Kg), urine Na+ meq/L, FENa, Serum BUN/Cr
- urine osmolairty --> less than 350
- urine Na+ more than 40
- FENa more than 2%
- Serum BUN/Cr less than 15
37
postrenal azotemia - mechansim
```
outflow obstruction (stones, BPH, neoplasia, congenital abnormalities) - develops only with bilateral obstruction
--> at the begining: increased pressure, low GFR, increased BUN:Cr ratio --> long standing: tubular damage ensue with decrease BUN reabsorption, BUN:CR increased
```
38
postrenal azotemia - urine osmolairty (mOsm/Kg), urine Na+ meq/L, FENa, Serum BUN/Cr
- urine osmolairty --> less than 350
- urine Na+ more than 40
- FENa more than 1% (mild) or 2% (severe)
- Serum BUN/Cr varies
39
Renal failure is the inability
to make urine and excrete nitrogenous wastes
40
Consequences of renal failure
```
mnemonic: MAD HUNGER
Metabolic acidosis
Dyslipidiemia (esp high TG)
Hyperkalemia
Uremia
Na+/H20 retention
Growth retardation and developmental delaty
Erytrhopoietin failure (anemia)
Renal osteodystrophy
```
41
Renal failure - dyslipidemia?
- maturation of HDL is impaired and its composition is altered
- clearance of triglyceride-rich lipoproteins and their atherogenic remnants is impaired
42
Uremia?
```
clinical syndrome marked by increased BUN:
Nausea and anorexia
Pericarditis
Asterixis
Encephalopathy
Platelet dysfunction
```
43
Chronic renal failure - due to
1. DM (MC)
2. Hypertension
3. Chronic glumerulonepritis (esp RPGN and Focal Segmental Glomerulosclerosis)
4. Cystic renal diasease
44
Acute interstitial renal nephritis is AKA
tubulointesritital nephritis
45
Acute interstitial renal nephritis (tubulointesritital nephritis) - clinical presentation/findings
```
IT CAN BE ASYMPTOMATIC
1. Fever
2. rash
3. hematuria (casts)
4. costovertebral angle tenderness
5. pyuria (classically eosinophils)
6. azotemia
7. oliguria
(days to weeks after the factor)
RESULTS IN ACUTE RENAL FAILURE
```
46
causes of Acute interstitial renal nephritis (tubulointesritital nephritis)
1. drugs that act as haptens, inducing hypersensitivity (eg. diuretics, penicillin derivatives, PPIs, sulfonamides, rifampin, NSAID)
2. Systemic infections (eg. mycoplasma)
3. Autoimmune diseases (eg. Sjogren syndrome, SLE, sarcoidosis)
47
example of a systemic infection that causes Acute interstitial renal nephritis (tubulointesritital nephritis)
mycoplasma
48
example of autoimmune diseases that cause Acute interstitial renal nephritis (tubulointesritital nephritis)
Sjogren syndrome, SLE, sarcoidosis
49
drugs that cause Acute interstitial renal nephritis (tubulointesritital nephritis)
drugs that act as haptens, inducing hypersensitivity (eg. diuretics, penicillin derivatives, PPIs, sulfonamides, rifampin, NSAID)
50
Acute interstitial renal nephritis (tubulointesritital nephritis) may progress to
renal papillary necrosis
51
renal papillary necrosis?
sloughing of necrotic renal failure
52
renal papillary necrosis - symptoms/findings
1. gross hematuria
2. proteinuria
3. flank pain
53
causes of renal papillary necrosis
1. Sickle cell disease or trait
2. acute pyelonephritis
3. NSAID (or phenacetin)
4. DM
5. Acute interstitial renal nephritis
May be triggered by recent infection or immune stimulus
54
Renal papillary necrosis can be triggered by
1. recent infection
| 2. immune stimulus
55
Acute intersitial nephritis - treatment
stop the factor (eg. cessation of the drug)
56
MCC of acute kidney injury in hospitalized patients
Acute tubular necrosis
57
Acute tubular necrosis - prognosis
can be fatal, esp during initial oligurinc phase
58
Acute tubular necrosis - FENa
more than 2%
59
Acute tubular necrosis - key finding
granular (muddy brown) casts
60
Acute tubular necrosis - stages
1. inciting event
2. Maintenance phase - oliguric
3. Recovery phase - oliguric
61
Acute tubular necrosis - duration of maintenance phase
1-3 weeks
62
Acute tubular necrosis - maintenance phase - risk for
1. hypokalemia
2. metabolic acidosis
3. uremia
63
Acute tubular necrosis - Recovery phase - findings
BUN and creatinine fall
64
Acute tubular necrosis - recovery phase - risk for
hypokalemia
65
Acute tubular necrosis can be caused by .... (groups)
1. ischemic factors
| 2. nephrotoxic factors
66
Acute tubular necrosis - ischemic factors - mechanism
2ry to low RBF (eg. hypotnesion, shock, sepsis, hemorrhage, HF) (often preceded by renal azotemia) --> Resutls in death of tubular cells that may slough into tubular lumen
67
Acute tubular necrosis - areas that are highly susceptible to ischemic injury
1. PCT
| 2. Thich ascending limb
68
Acute tubular necrosis - nephrotoxic factors - mechanism
2ry to injury resulting from toxic substance (eg. aminglycosides, radiocontrasts agents, lead, cisplatin), crush injury (myoglobinuria), hemoglobinuria
69
Acute tubular necrosis - areas that are highly susceptible to nephrotoxic injury
PCT
70
Acute tubular necrosis - areas that are highly susceptible to ischemic injury vs nephrotoxic injury
ischemic injury --> PCT, Thich ascending limb
| nephrotoxic injury --> PCT
71
Renal osteodystrophy?
hypocalcemia, hyperphosphatemia and failure of vitD hydroxylation associated with chronic renal disease --> secondary hyperparathyroidism
ALSO hyperphosphatemia decreases serum Ca2+ by causing tissue calcifications wheres low Vit D --> low intestinal Ca2+ absorption
72
Renal osteodystrophy causes ..... (on bones)
subperiosteal thinning of bones
73
Hydronephrosis - defnition
distention/dilation of renal pelvis and calyces
74
causes of hydronephrosis
- usually caused by urinary tract obstruction (stones, PBH, cervical cancer, injury to ureter)
- orher causes --> retroperitoneal fibrosis, vesicourateral reflex
75
hydronephrosis dilation occurs .. (location)
proximally to the site of pathology
76
hydronephrosis leads to ... (appearance)
compression and possible atrophy of renal cortex and atrophy
77
hydronephrosis - serum creatinine elevation?
only if obstruction is bilateral or if patient has only one kidney
78
hallmark of nephritic syndrome
glumerular inflammation and bleeding
