SlideShare a Scribd company logo
1 of 31
RENAL SYSTEM
RENALTUBULAR ACIDOSIS
INTRODUCTION
 Lungs and Kidneys are responsible for Normal acid
base balance
 Alveolar ventilation removes CO2
 Kidneys reabsorb filtered Bicarbonate and excrete
a daily quantity of Hydrogen ion equal to that
produced by the metabolism of dietary proteins.
 Hydrogen ions are excreted primarily by
enhancing the excretion of ammonium ions in the
urine
DEFINITION
The term "renal tubular acidosis" (RTA)
refers to a group of disorders in
which, despite a relatively well-
preserved glomerular filtration
rate, metabolic acidosis develops
because of defects in the ability of the
renal tubules to perform the normal
functions required to maintain acid-
base balance.
INCIDENCE
 Predominant age: All ages
 Predominant sex: Male > Female (with
regard to type II RTA with isolated defect
in bicarbonate reabsorption)
TYPES
 Distal / type 1 RTA
 Proximal / type 2 RTA
 Hypoaldosteronism / type 4 RTA
 Type 3 / mixed RTA (not in use)
Type 1-Distal RTA
Distal RTA (dRTA) is the classical form
of RTA. Inability of the distal tubule to
acidify the urine. Due to impaired
hydrogen ion secretion, increased backleak
of secreted hydrogen ions, or impaired
sodium reabsorption (causing less negative
potential in the lumen and hence less
hydrogen/potassium secretion).
 Urine pH >5.5.
PATHOPHYSIOLOGY
 failure of acid secretion by the alpha
intercalated cells of the cortical collecting
duct of the distal nephron.
 it leads to an inability to acidify the urine to
a pH <5.3
 renal excretion is the primary means of
eliminating acid from the body, there is
consequently a tendency towards acidemia
 There is an inability to excrete H+
while K+ cannot be reabsorbed, leading to
acidemia (as H+ builds up in the body) and
hypokalemia (as K+ cannot be reabsorbed).
 the substance of the kidney develops stones
bilaterally
RISK FACTORS
Genetics
Autosomal dominant or recessive. May
occur in association with other genetic
diseases (e.g., Ehlers-Danlos
syndrome, hereditary elliptocytosis, or
sickle cell nephropathy). The autosomal
recessive form is associated with
sensorineural deafness.
ETIOLOGY
• Genetic
• Sporadic
• Autoimmune diseases:
rheumatoid arthritis (RA), SLE
• Hematologic diseases:
Sickle cell disease, hereditary
elliptocytosis
• Medications:
Amphotericin B, lithium, K+-
sparing diuretics
• Toxins:
Toluene, glue
• Hypercalciuria, diseases
causing nephrocalcinosis
• Vitamin D intoxication
• Medullary cystic disease
• Glycogenosis type III
• Fabry disease
• Wilson disease
• Hypergammaglobulinemic
syndrome
• Obstructive uropathy
• Chronic pyelonephritis
• Chronic renal transplant
rejection
• Leprosy
• Hepatic cirrhosis
• Malnutrition
CLINICAL MANIFESTATIONS
 non-anion gap metabolic
acidosis
 growth failure
 nephrocalcinosis
 hypercalciuria
Defect of the proximal tubule in
bicarbonate (HCO3) reabsorption.
HCO3 fully reabsorbed only when
plasma HCO3 concentration <15–16
mEq/L (compared with normal
threshold of 24 mEq/L). Urine pH <5.5
unless plasma HCO3 above
reabsorptive threshold.
 It is caused by a failure of the proximal
tubular cells to reabsorb filtered
bicarbonate from the urine, leading to
urinary bicarbonate wasting and
subsequent acidemia.
 The distal intercalated cells function
normally, so the acidemia is less severe
than dRTA and the urine can acidify to a
pH <5.3.
 it is usually associated with a generalized
dysfunction of the proximal tubular cells
called Fanconi's syndrome.
Clinical manifestations -
phosphaturia, glycosuria, amin
oaciduria, uricosuria, and
tubular proteinuria. The
principal feature of Fanconi's
syndrome is bone
demineralization due to
phosphate wasting.
-Autosomal dominant form is rare.
-Autosomal recessive form is
associated with ophthalmologic
abnormalities and mental
retardation. Occurs in Fanconi
syndrome, which is associated with
several genetic diseases
 Diseases associated with Fanconi syndrome
 Sporadic
 Multiple myeloma & other dysproteinemic
states
 Amyloidosis
 Heavy-metal poisoning
 Medications:
Acetazolamide, sulfanilamide, ifosfamide, o
utdated tetracycline, topiramate
 Autoimmune disease
 Interstitial renal disease
 Nephrotic syndrome
 Congenital heart disease
 Defects in calcium metabolism
 growth failure in the 1st year of life
 polyuria
 dehydration
 anorexia
 vomiting
 constipation
 hypotonia
 Patients with primary Fanconi
syndrome will have additional
symptoms
 Those with systemic diseases will
present with additional signs and
symptoms specific to their underlying
disease
Type 3 RTA-Combined
proximal and distal RTA
Extremely rare autosomal recessive syndrome
with features of both type I and type II
(juvenile RTA).
Combined dRTA and pRTA is also observed as
the result of inherited carbonic anhydrase II
deficiency. Mutations in the gene encoding this
enzyme give rise to an autosomal recessive
syndrome of osteopetrosis, renal tubular
acidosis, cerebral calcification, and mental
retardation.
•
Type 4 RTA
 Due to aldosterone resistance or deficiency
that results in hyperkalemia.
 It was included in the classification of renal
tubular acidoses as it is associated with a
mild (normal anion gap) metabolic acidosis
due to a physiological reduction in
proximal tubular ammonium excretion
(impaired ammoniagenesis), which is
secondary to hypoaldosteronism, and
results in a decrease in urine buffering
capacity.
 Urine pH <5.5.
RISK FACTORS
Some cases familial, such as
pseudohypoaldosteronism type
I (autosomal dominant)
ETIOLOGY
 Medications: Nonsteroidal anti-inflammatory
drugs, angiotensin-converting enzyme
inhibitors, angiotensin receptor
blockers, heparin/LMW heparin, calcineurin
inhibitors (tacrolimus, cyclosporine) (1)
 Diabetic nephropathy
 Obstructive nephropathy
 Nephrosclerosis due to hypertension
 Tubulointerstitial nephropathies
 Primary adrenal insufficiency
 Pseudohypoaldosteronism(end-organ
resistance to aldosterone)
 Gordon syndrome
 Sickle cell nephropathy
CLINICAL MANIFESTATIONS
 with growth failure in the first few years of
life
 Polyuria
 Dehydration
 Rarely, with life-threatening hyperkalemia
 Patients with obstructive uropathies may
present acutely with signs and symptoms of
pyelonephritis
 hyperkalemic non-anion gap metabolic
acidosis
 Alkaline or acidic urine
 Elevated urine sodium levels &
inappropriately low urine potassium levels
reflect the absence of aldosterone effect.
History collection
 Often asymptomatic (particularly
type IV)
 Failure to thrive in children
 Anorexia, nausea/vomiting
 Weakness or polyuria (due to
hypokalemia)
 Rickets in children
 Osteomalacia in adults
 Constipation
 Polydipsia
 Electrolytes - hyperchloremic metabolic
acidosis.
 Plasma anion gap normal (anion gap = Na - [Cl +
HCO3])
 Hypokalemia or normokalemia
 Hyperkalemia
 Plasma HCO3 (in untreated RTA)
 Blood urea nitrogen and creatinine usually
normal (rules out renal failure as cause of
acidosis)
 Urine pH: Inappropriately alkaline (pH >5.5)
 Urine culture: Rule out UTI with urea-splitting
organism and chronic infection
 Urine anion gap: Reflects unmeasured urine
anions, so inversely related to urine NH4+ (or
acid) excretion. Positive urine anion gap in an
acidemic patient indicates impaired renal acid
excretion.
 Urine calcium:
 High in type I
 Typically normal in type II
 A renal ultrasound - to identify underlying
structural abnormalities such as obstructive
uropathies as well as to determine the presence
of nephrocalcinosis.
 correction of the acidemia with oral sodium
bicarbonate, sodium citrate or potassium citrate.
This will reverse bone demineralization
 Hypokalemia and urinary stone formation and
nephrocalcinosis can be treated with potassium
citrate tablets
 Patients with proximal RTA often require large
quantities of bicarbonate, up to 20 mEq/kg/24 hr
in the form of sodium bicarbonate or sodium
citrate solution
 The base requirement for distal RTAs is generally in
the range of 2-4 mEq/kg/24 hr.
 Patients with Fanconi syndrome generally require
phosphate supplementation .
 Patients with distal RTA should be monitored for the
development of hypercalciuria. Symptomatic
hypercalciuria, nephrocalcinosis, or nephrolithiasis
may require thiazide diuretics to decrease urine
calcium excretion.
 Patients with type IV RTA may require chronic
treatment for hyperkalemia with sodium-potassium
exchange resin
 Administration of sufficient bicarbonate to reverse
acidosis stops bone dissolution and the
hypercalciuria.
 Proximal RTA is treated with both bicarbonate and
oral phosphate supplements to heal bone disease.
 Vitamin D is needed to offset the secondary
hyperparathyroidism that complicates oral
phosphate therapy
 The mainstay of therapy in all forms of RTA is
bicarbonate replacement .
PROGNOSIS
• Depends on associated
disease, otherwise good with therapy
• Transient forms of all types of RTA
may occur.
COMPLICATIONS
• Nephrocalcinosis, nephrolithiasis
(type I)
• Hypercalciuria (type I)
• Hypokalemia (type I, type II if given
bicarbonate)
• Hyperkalemia (type IV, some causes
of type I)
• Osteomalacia (type II due to
phosphate wasting)
renal tubular acidosis (RTA)

More Related Content

What's hot

Hemolytic uremic syndrome
Hemolytic uremic syndromeHemolytic uremic syndrome
Hemolytic uremic syndrome
Najib Suhrabi
 
Hiv associated nephropathy(Dr. sood)
Hiv associated nephropathy(Dr. sood)Hiv associated nephropathy(Dr. sood)
Hiv associated nephropathy(Dr. sood)
polobismuth
 

What's hot (20)

Hepatorenal syndrome
Hepatorenal syndromeHepatorenal syndrome
Hepatorenal syndrome
 
Hyponatremia
HyponatremiaHyponatremia
Hyponatremia
 
Pediatric Acute Liver Failure
Pediatric Acute Liver FailurePediatric Acute Liver Failure
Pediatric Acute Liver Failure
 
Approach to ascites
Approach to ascitesApproach to ascites
Approach to ascites
 
Renal tubular acidosis
Renal tubular acidosisRenal tubular acidosis
Renal tubular acidosis
 
Fulminant hepatic failure (fhf)
Fulminant hepatic failure (fhf)Fulminant hepatic failure (fhf)
Fulminant hepatic failure (fhf)
 
Acute kidney injury
Acute kidney injuryAcute kidney injury
Acute kidney injury
 
Hepatic Encephalopathy -Pathophysiology,Evaluation And Management
Hepatic Encephalopathy -Pathophysiology,Evaluation And ManagementHepatic Encephalopathy -Pathophysiology,Evaluation And Management
Hepatic Encephalopathy -Pathophysiology,Evaluation And Management
 
Hemolytic uremic syndrome
Hemolytic uremic syndromeHemolytic uremic syndrome
Hemolytic uremic syndrome
 
chronic kidney disease.ppt
chronic kidney disease.pptchronic kidney disease.ppt
chronic kidney disease.ppt
 
Autoimmune hepatitis rajesh
Autoimmune hepatitis rajeshAutoimmune hepatitis rajesh
Autoimmune hepatitis rajesh
 
Hyponatremia ppt .final
Hyponatremia ppt .finalHyponatremia ppt .final
Hyponatremia ppt .final
 
Lupus nephritis 2016
Lupus nephritis 2016Lupus nephritis 2016
Lupus nephritis 2016
 
Hiv associated nephropathy(Dr. sood)
Hiv associated nephropathy(Dr. sood)Hiv associated nephropathy(Dr. sood)
Hiv associated nephropathy(Dr. sood)
 
Acute kidney injury in children 2018
Acute kidney injury in children 2018Acute kidney injury in children 2018
Acute kidney injury in children 2018
 
Wilson's disease (wilson)
Wilson's disease (wilson)Wilson's disease (wilson)
Wilson's disease (wilson)
 
Hepatic encephalopathy
Hepatic encephalopathyHepatic encephalopathy
Hepatic encephalopathy
 
Acute kidney injury
Acute kidney injuryAcute kidney injury
Acute kidney injury
 
Pancytopenia
PancytopeniaPancytopenia
Pancytopenia
 
Lupus nephritis
Lupus nephritisLupus nephritis
Lupus nephritis
 

Similar to renal tubular acidosis (RTA)

Chronic renal failure(2010505)
Chronic renal failure(2010505)Chronic renal failure(2010505)
Chronic renal failure(2010505)
internalmed
 
Chronic renal failure(2010505)
Chronic renal failure(2010505)Chronic renal failure(2010505)
Chronic renal failure(2010505)
internalmed
 
Genetic based renal transport disorder dr rani shal
Genetic based renal transport disorder dr rani shalGenetic based renal transport disorder dr rani shal
Genetic based renal transport disorder dr rani shal
FarragBahbah
 

Similar to renal tubular acidosis (RTA) (20)

Rta dr mahtab
Rta dr mahtabRta dr mahtab
Rta dr mahtab
 
Renal Tubular Acidosis
Renal Tubular AcidosisRenal Tubular Acidosis
Renal Tubular Acidosis
 
RENAL TUBULAR ACIDOSIS.pptx
RENAL TUBULAR ACIDOSIS.pptxRENAL TUBULAR ACIDOSIS.pptx
RENAL TUBULAR ACIDOSIS.pptx
 
Renal tubular acidosis
Renal tubular acidosisRenal tubular acidosis
Renal tubular acidosis
 
Renal tubular acidosis ppt
Renal tubular acidosis pptRenal tubular acidosis ppt
Renal tubular acidosis ppt
 
Hereditary tubulopathy
Hereditary tubulopathyHereditary tubulopathy
Hereditary tubulopathy
 
Renal tubular acidosis
Renal tubular acidosisRenal tubular acidosis
Renal tubular acidosis
 
Fluid and Eletrolyte imbalance and nursing care.
Fluid and Eletrolyte imbalance and nursing care.Fluid and Eletrolyte imbalance and nursing care.
Fluid and Eletrolyte imbalance and nursing care.
 
tubular diseases and analysis of urinary calculi
tubular diseases and analysis of urinary calculitubular diseases and analysis of urinary calculi
tubular diseases and analysis of urinary calculi
 
Renal tubular acidosis (pediatrics)
Renal tubular acidosis (pediatrics)Renal tubular acidosis (pediatrics)
Renal tubular acidosis (pediatrics)
 
Chronic renal failure(2010505)
Chronic renal failure(2010505)Chronic renal failure(2010505)
Chronic renal failure(2010505)
 
Chronic renal failure(2010505)
Chronic renal failure(2010505)Chronic renal failure(2010505)
Chronic renal failure(2010505)
 
Renal failure history and examination
Renal failure history and examinationRenal failure history and examination
Renal failure history and examination
 
Renal disase [autosaved]
Renal disase [autosaved]Renal disase [autosaved]
Renal disase [autosaved]
 
acute and chronic renal failure
acute and chronic renal failureacute and chronic renal failure
acute and chronic renal failure
 
RENAL TUBULAR ACIDOSIS.pptx
RENAL TUBULAR ACIDOSIS.pptxRENAL TUBULAR ACIDOSIS.pptx
RENAL TUBULAR ACIDOSIS.pptx
 
Genetic based renal transport disorder dr rani shal
Genetic based renal transport disorder dr rani shalGenetic based renal transport disorder dr rani shal
Genetic based renal transport disorder dr rani shal
 
Genetic based renal transport disorder dr rani shal
Genetic based renal transport disorder dr rani shalGenetic based renal transport disorder dr rani shal
Genetic based renal transport disorder dr rani shal
 
clinical MANAGEMENT OF HYPONATRAEMIA.pptx
clinical MANAGEMENT OF HYPONATRAEMIA.pptxclinical MANAGEMENT OF HYPONATRAEMIA.pptx
clinical MANAGEMENT OF HYPONATRAEMIA.pptx
 
Hypokalemia paralyzing revealing a rare association of autoimmune diseases: t...
Hypokalemia paralyzing revealing a rare association of autoimmune diseases: t...Hypokalemia paralyzing revealing a rare association of autoimmune diseases: t...
Hypokalemia paralyzing revealing a rare association of autoimmune diseases: t...
 

More from Ria Saira

renal replacement therapies
renal replacement therapiesrenal replacement therapies
renal replacement therapies
Ria Saira
 
congenital anomalies of renal system
congenital anomalies of renal systemcongenital anomalies of renal system
congenital anomalies of renal system
Ria Saira
 

More from Ria Saira (12)

Renal system complete
Renal system completeRenal system complete
Renal system complete
 
vesicourethral reflux
vesicourethral refluxvesicourethral reflux
vesicourethral reflux
 
Hemorrhage in children
Hemorrhage in childrenHemorrhage in children
Hemorrhage in children
 
pediatric Drug administration
pediatric Drug administrationpediatric Drug administration
pediatric Drug administration
 
renal replacement therapies
renal replacement therapiesrenal replacement therapies
renal replacement therapies
 
Continuing nursing education
Continuing nursing educationContinuing nursing education
Continuing nursing education
 
terminal illness and death
terminal illness and deathterminal illness and death
terminal illness and death
 
hospitalised child
hospitalised childhospitalised child
hospitalised child
 
renal failure
renal failurerenal failure
renal failure
 
few glomerular diseases
few glomerular diseasesfew glomerular diseases
few glomerular diseases
 
UTI in children
UTI in childrenUTI in children
UTI in children
 
congenital anomalies of renal system
congenital anomalies of renal systemcongenital anomalies of renal system
congenital anomalies of renal system
 

Recently uploaded

SPLICE Working Group: Reusable Code Examples
SPLICE Working Group:Reusable Code ExamplesSPLICE Working Group:Reusable Code Examples
SPLICE Working Group: Reusable Code Examples
Peter Brusilovsky
 

Recently uploaded (20)

demyelinated disorder: multiple sclerosis.pptx
demyelinated disorder: multiple sclerosis.pptxdemyelinated disorder: multiple sclerosis.pptx
demyelinated disorder: multiple sclerosis.pptx
 
How to Send Pro Forma Invoice to Your Customers in Odoo 17
How to Send Pro Forma Invoice to Your Customers in Odoo 17How to Send Pro Forma Invoice to Your Customers in Odoo 17
How to Send Pro Forma Invoice to Your Customers in Odoo 17
 
VAMOS CUIDAR DO NOSSO PLANETA! .
VAMOS CUIDAR DO NOSSO PLANETA!                    .VAMOS CUIDAR DO NOSSO PLANETA!                    .
VAMOS CUIDAR DO NOSSO PLANETA! .
 
TỔNG HỢP HƠN 100 ĐỀ THI THỬ TỐT NGHIỆP THPT TOÁN 2024 - TỪ CÁC TRƯỜNG, TRƯỜNG...
TỔNG HỢP HƠN 100 ĐỀ THI THỬ TỐT NGHIỆP THPT TOÁN 2024 - TỪ CÁC TRƯỜNG, TRƯỜNG...TỔNG HỢP HƠN 100 ĐỀ THI THỬ TỐT NGHIỆP THPT TOÁN 2024 - TỪ CÁC TRƯỜNG, TRƯỜNG...
TỔNG HỢP HƠN 100 ĐỀ THI THỬ TỐT NGHIỆP THPT TOÁN 2024 - TỪ CÁC TRƯỜNG, TRƯỜNG...
 
The Story of Village Palampur Class 9 Free Study Material PDF
The Story of Village Palampur Class 9 Free Study Material PDFThe Story of Village Palampur Class 9 Free Study Material PDF
The Story of Village Palampur Class 9 Free Study Material PDF
 
Supporting Newcomer Multilingual Learners
Supporting Newcomer  Multilingual LearnersSupporting Newcomer  Multilingual Learners
Supporting Newcomer Multilingual Learners
 
Mattingly "AI and Prompt Design: LLMs with NER"
Mattingly "AI and Prompt Design: LLMs with NER"Mattingly "AI and Prompt Design: LLMs with NER"
Mattingly "AI and Prompt Design: LLMs with NER"
 
The Liver & Gallbladder (Anatomy & Physiology).pptx
The Liver &  Gallbladder (Anatomy & Physiology).pptxThe Liver &  Gallbladder (Anatomy & Physiology).pptx
The Liver & Gallbladder (Anatomy & Physiology).pptx
 
8 Tips for Effective Working Capital Management
8 Tips for Effective Working Capital Management8 Tips for Effective Working Capital Management
8 Tips for Effective Working Capital Management
 
How To Create Editable Tree View in Odoo 17
How To Create Editable Tree View in Odoo 17How To Create Editable Tree View in Odoo 17
How To Create Editable Tree View in Odoo 17
 
Stl Algorithms in C++ jjjjjjjjjjjjjjjjjj
Stl Algorithms in C++ jjjjjjjjjjjjjjjjjjStl Algorithms in C++ jjjjjjjjjjjjjjjjjj
Stl Algorithms in C++ jjjjjjjjjjjjjjjjjj
 
DEMONSTRATION LESSON IN ENGLISH 4 MATATAG CURRICULUM
DEMONSTRATION LESSON IN ENGLISH 4 MATATAG CURRICULUMDEMONSTRATION LESSON IN ENGLISH 4 MATATAG CURRICULUM
DEMONSTRATION LESSON IN ENGLISH 4 MATATAG CURRICULUM
 
diagnosting testing bsc 2nd sem.pptx....
diagnosting testing bsc 2nd sem.pptx....diagnosting testing bsc 2nd sem.pptx....
diagnosting testing bsc 2nd sem.pptx....
 
Observing-Correct-Grammar-in-Making-Definitions.pptx
Observing-Correct-Grammar-in-Making-Definitions.pptxObserving-Correct-Grammar-in-Making-Definitions.pptx
Observing-Correct-Grammar-in-Making-Definitions.pptx
 
UChicago CMSC 23320 - The Best Commit Messages of 2024
UChicago CMSC 23320 - The Best Commit Messages of 2024UChicago CMSC 23320 - The Best Commit Messages of 2024
UChicago CMSC 23320 - The Best Commit Messages of 2024
 
Andreas Schleicher presents at the launch of What does child empowerment mean...
Andreas Schleicher presents at the launch of What does child empowerment mean...Andreas Schleicher presents at the launch of What does child empowerment mean...
Andreas Schleicher presents at the launch of What does child empowerment mean...
 
Spring gala 2024 photo slideshow - Celebrating School-Community Partnerships
Spring gala 2024 photo slideshow - Celebrating School-Community PartnershipsSpring gala 2024 photo slideshow - Celebrating School-Community Partnerships
Spring gala 2024 photo slideshow - Celebrating School-Community Partnerships
 
e-Sealing at EADTU by Kamakshi Rajagopal
e-Sealing at EADTU by Kamakshi Rajagopale-Sealing at EADTU by Kamakshi Rajagopal
e-Sealing at EADTU by Kamakshi Rajagopal
 
An overview of the various scriptures in Hinduism
An overview of the various scriptures in HinduismAn overview of the various scriptures in Hinduism
An overview of the various scriptures in Hinduism
 
SPLICE Working Group: Reusable Code Examples
SPLICE Working Group:Reusable Code ExamplesSPLICE Working Group:Reusable Code Examples
SPLICE Working Group: Reusable Code Examples
 

renal tubular acidosis (RTA)

  • 2. INTRODUCTION  Lungs and Kidneys are responsible for Normal acid base balance  Alveolar ventilation removes CO2  Kidneys reabsorb filtered Bicarbonate and excrete a daily quantity of Hydrogen ion equal to that produced by the metabolism of dietary proteins.  Hydrogen ions are excreted primarily by enhancing the excretion of ammonium ions in the urine
  • 3. DEFINITION The term "renal tubular acidosis" (RTA) refers to a group of disorders in which, despite a relatively well- preserved glomerular filtration rate, metabolic acidosis develops because of defects in the ability of the renal tubules to perform the normal functions required to maintain acid- base balance.
  • 4.
  • 5. INCIDENCE  Predominant age: All ages  Predominant sex: Male > Female (with regard to type II RTA with isolated defect in bicarbonate reabsorption)
  • 6. TYPES  Distal / type 1 RTA  Proximal / type 2 RTA  Hypoaldosteronism / type 4 RTA  Type 3 / mixed RTA (not in use)
  • 7. Type 1-Distal RTA Distal RTA (dRTA) is the classical form of RTA. Inability of the distal tubule to acidify the urine. Due to impaired hydrogen ion secretion, increased backleak of secreted hydrogen ions, or impaired sodium reabsorption (causing less negative potential in the lumen and hence less hydrogen/potassium secretion).  Urine pH >5.5.
  • 8. PATHOPHYSIOLOGY  failure of acid secretion by the alpha intercalated cells of the cortical collecting duct of the distal nephron.  it leads to an inability to acidify the urine to a pH <5.3  renal excretion is the primary means of eliminating acid from the body, there is consequently a tendency towards acidemia  There is an inability to excrete H+ while K+ cannot be reabsorbed, leading to acidemia (as H+ builds up in the body) and hypokalemia (as K+ cannot be reabsorbed).  the substance of the kidney develops stones bilaterally
  • 9. RISK FACTORS Genetics Autosomal dominant or recessive. May occur in association with other genetic diseases (e.g., Ehlers-Danlos syndrome, hereditary elliptocytosis, or sickle cell nephropathy). The autosomal recessive form is associated with sensorineural deafness.
  • 10. ETIOLOGY • Genetic • Sporadic • Autoimmune diseases: rheumatoid arthritis (RA), SLE • Hematologic diseases: Sickle cell disease, hereditary elliptocytosis • Medications: Amphotericin B, lithium, K+- sparing diuretics • Toxins: Toluene, glue • Hypercalciuria, diseases causing nephrocalcinosis • Vitamin D intoxication • Medullary cystic disease • Glycogenosis type III • Fabry disease • Wilson disease • Hypergammaglobulinemic syndrome • Obstructive uropathy • Chronic pyelonephritis • Chronic renal transplant rejection • Leprosy • Hepatic cirrhosis • Malnutrition
  • 11. CLINICAL MANIFESTATIONS  non-anion gap metabolic acidosis  growth failure  nephrocalcinosis  hypercalciuria
  • 12. Defect of the proximal tubule in bicarbonate (HCO3) reabsorption. HCO3 fully reabsorbed only when plasma HCO3 concentration <15–16 mEq/L (compared with normal threshold of 24 mEq/L). Urine pH <5.5 unless plasma HCO3 above reabsorptive threshold.
  • 13.  It is caused by a failure of the proximal tubular cells to reabsorb filtered bicarbonate from the urine, leading to urinary bicarbonate wasting and subsequent acidemia.  The distal intercalated cells function normally, so the acidemia is less severe than dRTA and the urine can acidify to a pH <5.3.  it is usually associated with a generalized dysfunction of the proximal tubular cells called Fanconi's syndrome.
  • 14. Clinical manifestations - phosphaturia, glycosuria, amin oaciduria, uricosuria, and tubular proteinuria. The principal feature of Fanconi's syndrome is bone demineralization due to phosphate wasting.
  • 15. -Autosomal dominant form is rare. -Autosomal recessive form is associated with ophthalmologic abnormalities and mental retardation. Occurs in Fanconi syndrome, which is associated with several genetic diseases
  • 16.  Diseases associated with Fanconi syndrome  Sporadic  Multiple myeloma & other dysproteinemic states  Amyloidosis  Heavy-metal poisoning  Medications: Acetazolamide, sulfanilamide, ifosfamide, o utdated tetracycline, topiramate  Autoimmune disease  Interstitial renal disease  Nephrotic syndrome  Congenital heart disease  Defects in calcium metabolism
  • 17.  growth failure in the 1st year of life  polyuria  dehydration  anorexia  vomiting  constipation  hypotonia  Patients with primary Fanconi syndrome will have additional symptoms  Those with systemic diseases will present with additional signs and symptoms specific to their underlying disease
  • 18. Type 3 RTA-Combined proximal and distal RTA Extremely rare autosomal recessive syndrome with features of both type I and type II (juvenile RTA). Combined dRTA and pRTA is also observed as the result of inherited carbonic anhydrase II deficiency. Mutations in the gene encoding this enzyme give rise to an autosomal recessive syndrome of osteopetrosis, renal tubular acidosis, cerebral calcification, and mental retardation. •
  • 19. Type 4 RTA  Due to aldosterone resistance or deficiency that results in hyperkalemia.  It was included in the classification of renal tubular acidoses as it is associated with a mild (normal anion gap) metabolic acidosis due to a physiological reduction in proximal tubular ammonium excretion (impaired ammoniagenesis), which is secondary to hypoaldosteronism, and results in a decrease in urine buffering capacity.  Urine pH <5.5.
  • 20. RISK FACTORS Some cases familial, such as pseudohypoaldosteronism type I (autosomal dominant)
  • 21. ETIOLOGY  Medications: Nonsteroidal anti-inflammatory drugs, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, heparin/LMW heparin, calcineurin inhibitors (tacrolimus, cyclosporine) (1)  Diabetic nephropathy  Obstructive nephropathy  Nephrosclerosis due to hypertension  Tubulointerstitial nephropathies  Primary adrenal insufficiency  Pseudohypoaldosteronism(end-organ resistance to aldosterone)  Gordon syndrome  Sickle cell nephropathy
  • 22. CLINICAL MANIFESTATIONS  with growth failure in the first few years of life  Polyuria  Dehydration  Rarely, with life-threatening hyperkalemia  Patients with obstructive uropathies may present acutely with signs and symptoms of pyelonephritis  hyperkalemic non-anion gap metabolic acidosis  Alkaline or acidic urine  Elevated urine sodium levels & inappropriately low urine potassium levels reflect the absence of aldosterone effect.
  • 23. History collection  Often asymptomatic (particularly type IV)  Failure to thrive in children  Anorexia, nausea/vomiting  Weakness or polyuria (due to hypokalemia)  Rickets in children  Osteomalacia in adults  Constipation  Polydipsia
  • 24.  Electrolytes - hyperchloremic metabolic acidosis.  Plasma anion gap normal (anion gap = Na - [Cl + HCO3])  Hypokalemia or normokalemia  Hyperkalemia  Plasma HCO3 (in untreated RTA)  Blood urea nitrogen and creatinine usually normal (rules out renal failure as cause of acidosis)  Urine pH: Inappropriately alkaline (pH >5.5)  Urine culture: Rule out UTI with urea-splitting organism and chronic infection
  • 25.  Urine anion gap: Reflects unmeasured urine anions, so inversely related to urine NH4+ (or acid) excretion. Positive urine anion gap in an acidemic patient indicates impaired renal acid excretion.  Urine calcium:  High in type I  Typically normal in type II  A renal ultrasound - to identify underlying structural abnormalities such as obstructive uropathies as well as to determine the presence of nephrocalcinosis.
  • 26.  correction of the acidemia with oral sodium bicarbonate, sodium citrate or potassium citrate. This will reverse bone demineralization  Hypokalemia and urinary stone formation and nephrocalcinosis can be treated with potassium citrate tablets  Patients with proximal RTA often require large quantities of bicarbonate, up to 20 mEq/kg/24 hr in the form of sodium bicarbonate or sodium citrate solution
  • 27.  The base requirement for distal RTAs is generally in the range of 2-4 mEq/kg/24 hr.  Patients with Fanconi syndrome generally require phosphate supplementation .  Patients with distal RTA should be monitored for the development of hypercalciuria. Symptomatic hypercalciuria, nephrocalcinosis, or nephrolithiasis may require thiazide diuretics to decrease urine calcium excretion.  Patients with type IV RTA may require chronic treatment for hyperkalemia with sodium-potassium exchange resin
  • 28.  Administration of sufficient bicarbonate to reverse acidosis stops bone dissolution and the hypercalciuria.  Proximal RTA is treated with both bicarbonate and oral phosphate supplements to heal bone disease.  Vitamin D is needed to offset the secondary hyperparathyroidism that complicates oral phosphate therapy  The mainstay of therapy in all forms of RTA is bicarbonate replacement .
  • 29. PROGNOSIS • Depends on associated disease, otherwise good with therapy • Transient forms of all types of RTA may occur.
  • 30. COMPLICATIONS • Nephrocalcinosis, nephrolithiasis (type I) • Hypercalciuria (type I) • Hypokalemia (type I, type II if given bicarbonate) • Hyperkalemia (type IV, some causes of type I) • Osteomalacia (type II due to phosphate wasting)