Title: Myasthenia Gravis
1(No Transcript)
2Learning objectives
- To understand the pathophysiologic basis for
vasoactive therapies for HRS - To become familiar with the diagnostic criteria
for HRS - To learn about therapeutic options for patients
with HRS
3- Sinusoidal portal hypertension, in the presence
of severe hepatic decompensation - Leads to splanchnic and systemic
vasodilatation-role of NO - Decreased effective arterial blood volume
- Activation of systemic vasoactive factors, such
as the renin-angiotensin system, the sympathetic
nervous system, and vasopressin aimed at
restoring arterial filling pressure. - Renal vasoconstriction increases concomitantly
(leukotrienes and endothelins), counterbalanced
by the intrarenal hyperproduction of vasodilating
prostaglandins. When this balance is lost renal
hemodynamics worsens, and hepatorenal syndrome
develops
439-year-old man with a history of heavy alcohol
abuse and cirrhosis but no other significant past
medical problems was admitted for treatment of
increasing ascites. He had no known history of
kidney disease He had jaundice, tense ascites,
severe leg edema, and mild to moderate
encephalopathy. He had no signs of fluid loss,
such as bleeding or diarrhea. The patient was
not taking any nephrotoxic medications.
5His AST and ALT were 202 U/L and 68 U/L,
respectively, and his initial serum creatinine
level was 62 micromoles/L and Na 123. Results
of serologic testing for antibody to hepatitis C
virus, hepatitis B surface antigen, IgM antibody
to hepatitis A virus, antinuclear antibodies, and
antibody to Sm nuclear antigen were negative.
The patient had no detectable paracetamol level,
and his ceruloplasmin level was normal.
6Between day 5 and day 14 of the patient's
hospitalization, his serum creatinine level
increased from 230 micromoles/L. No improvement
in renal function after volume expansion with
1.5L isotonic saline solution Microscopic
examination of his urine revealed fewer than 50
red blood cells per high-power field. Urine and
serum osmolality values were 354 mOsm/kg H2O and
246 mOsm/kg H2O Urine protein excretion was 246
mg/24 hr, and spot urine sodium level was 7
mmol/L. Renal ultrasound was normal.
Serum-ascites albumin gradient was 2.1 g/dL,
and PMN count 2
7International Ascites Club diagnostic criteria
for HRS
-
- Major criteria
- Chronic or acute hepatic disease and liver
failure with portal hypertension - Serum creatinine level gt133 micromoles/L or 24-hr
creatinine clearance lt40 mL/min - Absence of shock, ongoing bacterial infection,
recent use of nephrotoxic drugs, excessive fluid
or blood loss - No sustained improvement in renal function after
volume expansion with 1.5 L isotonic saline
solution - Proteinuria lt500 mg/day and no ultrasonographic
evidence of renal tract or parenchymal disease - Minor criteria
- Urine volume lt500 mL/day
- Urine sodium lt10 mEq/L
- Urine osmolality greater than plasma osmolality
- Urine red blood cell count lt50 per high-power
field - Serum sodium lt130 mEq/L
8Types of HRS
- Type I HRS is the more serious type
- defined by a rise in creatinine level to over
221 micromoles/L in less than 2 weeks (or at
least a 50 percent lowering of the creatinine
clearance to a value below 20 mL/min) median
survival of 2 weeks - Type II HRS is defined as less severe renal
insufficiency than that observed with type I
disease it is principally characterized by
ascites that is resistant to diuretics. median
survival of 3-6 months.
9Other Problems to be Excluded
- Prerenal azotemia from volume depletion(diuretic/G
I bleed/LVP) - Systemic infection/SBP(HRS type 1 develops in 15
) - Drug-induced nephrotoxicity aminoglycosides,
diuretics, iodine-containing contrast agents, and
nonsteroidals. ACE inhibitors, demeclocycline,
and dipyridamole. - Postrenal azotemia from outflow obstruction
- Renal vascular disease
- Glomerulonephritis, nonstreptococcal
postinfectious
10PRERENAL HRS ATN
SPOT Na lt10 lt10 gt30
Urine sediment Nil Nil Positive
Fluid challenge Responds Nil Nil
11 12Incidence
- HRS occurs in approximately 4 of patients with
cirrhosis who are decompensated, - With a cumulative probability of 8 per year,
which increases to 39 at 5 years. - In hospitalized patients with ascites, the
incidence rate is 7-15.
13Assessing renal perfusion
- Creatinine production may be substantially
reduced in this setting, due to the liver disease
and to decreased muscle mass and protein and meat
intake. - Creatinine clearance value obtained in patients
with renal insufficiency will tend to
overestimate the true GFR due to increased
creatinine secretion - Noninvasive techniques to assess the degree of
renal vasoconstriction duplex Doppler
ultrasonography.A high resistive index ( 0.70) is
indicative of renal vasoconstriction.
14Treatment options
- OLT
- Haemodialysis
- TIPSS
- Vasoactive Medical treatment
15OLT
- Liver transplantation carries the best chance for
long-term survival, but the rapid deterioration
associated with type 1 HRS means that many
patients die before an organ becomes available. - The systemic and neurohumoral abnormalities
associated with HRS also resolve in the first
postoperative month. - The hepatorenal syndrome is a prerenal disease,
as the kidneys are normal histologically
16Dialysis
- This is used most commonly in patients who are
awaiting liver transplantation, as dialysis
improves the priority score for the transplant. - Acute and potentially reversible hepatic insult
may benefit from dialysis, since renal function
will recover in parallel with improving hepatic
function. - Hemodialysis is frequently difficult to perform
in patients with hepatorenal syndrome since
decompensated hepatic function is associated with
hemodynamic instability.
17TIPSS
- The transjugular intrahepatic portosystemic shunt
(TIPS) has been used in the treatment of
refractory ascites. When used in this setting,
there may also be a delayed improvement in renal
function - There is much less information on the use of TIPS
in patients who fulfill criteria for the
hepatorenal syndrome - Overall, these results suggest that, in selected
patients with hepatorenal syndrome, TIPSS may
provide short-term benefit. Given the risks
associated with this procedure (particularly the
high incidence of encephalopathy), it should be
considered only as a last resort in patients who
are not a candidate for or are awaiting liver
transplantation.
18Medical treatment
- Hepatorenal syndrome was recalcitrant to medical
therapy for so many years that it is still
perceived by many physicians as untreatable. - Clearly, new therapies have significantly
brightened the short-term outlook for patients
with type 1 hepatorenal syndrome, and improvement
in short-term survival rates may lead to
increased opportunity for definitive therapy (ie,
liver transplantation).
19Vasoactive therapy
- Midodrine- octreotide- albumin regime
- Terlipressin plus albumin
20- Midodrine and octreotide Growing data suggest
that combination therapy with midodrine (a
selective alpha-1 adrenergic agonist) and
octreotide (a somatostatin analog) may be highly
effective and safe. - The rationale is midodrine (systemic
vasoconstrictor) and octreotide (inhibitor of
endogenous vasodilator release)will reverse the
pathophysiology
Angelie et al Hepatology 1999 Pomier-Layrargues
et al Hepatology 2003
21- Sinusoidal portal hypertension, in the presence
of severe hepatic decompensation - Leads to splanchnic and systemic
vasodilatation-role of NO - Decreased effective arterial blood volume
- Activation of systemic vasoactive factors, such
as the renin-angiotensin system, the sympathetic
nervous system, and vasopressin aimed at
restoring arterial filling pressure. - Renal vasoconstriction increases concomitantly
(leukotrienes and endothelins), counterbalanced
by the intrarenal hyperproduction of vasodilating
prostaglandins. When this balance is lost renal
hemodynamics worsens, and hepatorenal syndrome
develops
22Midodrine- octreotide- albumin regime
- Midodrine (7.5 mg by mouth every 8 hours)
- Octreotide (100 mg subcutaneously every 8 hours)
- Albumin (25 mg intravenously per day)
23Terlipressin plus albuminregime
- Terlipressin bolus(0.5mg/4h)-increase every 3
days if no response to 1-2mg/4h - Given until creatinine normalizes or for 15 days
- Albumin 1g/kg on day1,20-60g/d thereafter
Uriz et al J Hepatol 2000
24- In one prospective, nonrandomized study 21
patients were treated with terlipressin plus
albumin compared with terlipressin alone. - The group treated with terlipressin and albumin
had a 3-month survival rate of 50, compared to
10 for the terlipressin-only group.
Ortega et al hepatology 2002
25- A small cohort of nine patients with cirrhosis
and HRS were given Terlipressin and albumin until
the reversal of hepatorenal syndrome or for a
maximum of 15 days - Seven of the nine patients showed a reversal of
hepatorenal syndrome. There was also a marked
improvement in MAP. Plasma renin activity and
plasma norepinephrine decreased
Uriz et al J Hepatol 2000
26PREVENTION
- In patients with spontaneous bacterial
peritonitis, the administration of intravenous
albumin (1.5 g/kg) at the time of diagnosis of
infection and another dose of albumin (1.0 g/kg)
on day three of antibiotic treatment may reduce
the incidence of both renal impairment and
mortality during hospitalization and at three
months - Pentoxifylline (400 mg PO TID) may be preventive
in patients with severe alcoholic hepatitis -
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