DR. SHAFIQ AHMAD. TMO MEDICAL “B” UNIT. LRH, PESHAWAR. Case History.
TMO MEDICAL “B” UNIT.
A Nineteen years old thin boy presented with six months history of pain both the lumber areas with generalized abdominal cramps and body aches. He was also experiencing difficulty in walking, along with epigastric pain and occasional vomiting for the last two months.
No h/o loose motion, joints pains and fever.
A month ago he was again hospitalized in DHQ Nowshehra for vomiting and partially responded to anti-emetic and PPI.
He was a thin lean boy of average height, afebrile and normotensive. Systemic examination was unremarkable. Gait was normal although he was complaining of pain during walking and on standing from sitting position.
FULL BLOOD COUNT
with normal differential count
Ammonium chloride challenge test0.1 gm/kg Ammonium chloride was given orally and urinary and plasma pH recorded every two hrs. There was no drop in urinary pH below 5.4 tough the plasma pH fell to 7.30. This test confirmed the diagnosis of…….
Type I distal Renal Tubular
Its a systemic acidosis, resulting due to impaired ability of the Renal tubules to “ ACIDIFY” the urine normally and there will be little or no over all reduction in the Renal function test.
The disease is characterized by
Disease can present in different ways depending upon which aspect of Renal acid handling has been effected.
Hypokalemic , Hyperchloremic metabolic acidosis .
Inability to decrease urinary PH below 5.5
all this happens because:
may be idiopathetic
Various systemic diseases can lead to
AUTO IMMUNE DISEASE
RENAL TRANSPLANT REJECTION
( due to rickets in children and osteomalacia)
Decrease K+ , increase in Chloride
Decrease in ph HCo3 less than 21 mmol/L
enough Alkali should be given to filtrate the daily metabolic acid load. Usual range is 0.5 to 2mmol/kg/d.
The main defect is failure to secrete adequate H+ ions or selective defect in the P.C.T ability to reabsorb filtered HCO3.
About 90% of filtered bicarbonate is absorb by P.C.T, D.C.T has a limited ability to absorb bicarbonate .
When to much bicarbonate is left in the filtrate is delivered to D.C.T, that is over whelming the absorptive capacity of D.C.T, the tubules dose not function adequately and leads to bicarbonate Urea.
Eventually the distal delivery of filtered HCO3 declines because the Plasma HCO3levels drops as a result of progressive Urinary loss.
When Plasma HCO3 level drops to 15—18 mmol/L,the distal Nephrone will start function normally, as lower filtered load of HCO3 can be reabsorbed by P.C.T resulting in normal delivery of HCO3 to D.C.T and able to absorb all the HCO3 .
At this point HCO3 Urea disappears and Urinary PH can be acidic.
Hereditary Autosomal Dominant
Dysprotenanic slate i.e. myloma
( caused by Hypokalemic Myopathy)
S.Electrolytes S.K+ decrease
Cl- increase .
Decrease in Ca++ .
Decrease phosphate .
Decrease PH ,Decrease HCo3
PH increase 5.5
This type also called HYPER KALAMIC DISTAL RTA or HYPORENIMIC HYPOALDESTERONISM --- acquired disorder
weather there is decrease Aldasteron level or Renal Resistance to the effect of Aldasteron , it reduces the ability of distal Nephrone to secret H+ ions. Hyperkalaemia is directly due to loss of Aldasteron action . This causes suppression of Renal production of NH4 which further exacerbates the Acidosis
S.Na + - normal ( decrease if Addison )
PH + decrease
Aim: To decrease K+ as acidosis usually improve once Hyperkalemic block of NH4 production is removed
FLUDROCORTISONE 0.1---- 0.2 mg/day
This Minerlocorticoids replacement should not be the approach for the patients with hypertension or heart failure history