Dr. Aung Soe (a) Aung Kyaw Moe
World Kidney Day is celebrated in various parts of the world on the second Thursday of March every year since 2006. In that sense, today, March 10, Thursday, is the World Kidney Day 2016. Myanmar being a member of international community, commenced to hold WKD in 2009.
Normally, a pair of kidneys lie within our abdoman at right and left loins (flanks), constituting as essential vital organs, along with brain, heart, lungs, liver and so on. Healthy kidneys are precious not only for humans, but also for animals, as these excrete waste products of metabolism, wear and tear of body functions in the form of urine and keep physiology and haemodynamics normal. Along with lungs (expelling carbon dioxide) guts (defaecation), skin (perspiration), kidneys are essential for life. Should your kidneys fail to work normally, you may land up with dyspnoea and other breathing difficulties and so many ailments including faintings, loss of consciousness which may terminate your life!
There are so many kidney diseases including Nephrotic syndrome, Glomerulonephritis, Chronic kidney disease, Renal cell carcinoma, Acute tubular necrosis, Acute renal failure, Poly cystic kidney disease, Acute interstitial kidney disease and Nephrolithiasis. Out of them, I would like to elaborate two ailments which I encountered most frequently since 1960s up to now during my different assignments at various capacities across states and regions in Myanmar, as well as UNV UNDP carrier around South Asia and the Middle East. These are Renal Stones (Nephrolithiasis) and Acute Renal Failure (ARF), which I choose to mention today.
Acute Renal Failure
Causes of Acute Renal Failure include, (1) Prerenal failure caused by renal hypoperfusion, most often due to dehydration, excessive diuresis, Congestive Heart Failure or any type of shock. (2) Intrarenal (parenchymal disease): Acute tubular necrosis, acute glomerulonephritis, atherosclerosis/ thromboembolism, interstitial nephritis (- lactams, H2 blockers, NSAIDs). acyclovir, methotrexte, etc. (3) Postrenal obstruction: Prostate enlargement, bladder or ureteral obstruction (tumors, stones, lymph nodes, clot, fibrosis). Vascular: renal artery stenosis. aortic dissection, renal v. thrombosis.
Prerenal causes account for about one third of cases; intrarenal causes account for about half of cases (ATN is most common cause overall); postrenal causes account for 10 per cent; major vascular causes account for more than 5 per cent. ATN often develops in hospital settings and is multifactorial (hypoperfusion, myoglobin, nephrotoxins, and prerenal causes).
Common Presentaions of ARF are –
– Patient may be anuric, oliguric (less than 30 mL/hour of urine output), or nonoliguric. Signs and symptoms of uremia:
– Encephalopathy, confusion
– Fluid overload, edema, heart failure
– Metabolic aciodosis
– Hyperkalemia and arrhythmias (irregular heart-beats)
– Pericarditis / friction rub
– Fever may indicate a secondary infection
Diognosis is defined as a rise in BUN and creatinine, measured over hours to days (creatinine rising more than 0.5 when baseline is less than 3 mg/dL and rising more than 1.0 when baseline is more than 3.0).
Treatment is as follows:-
– Correct hydration, lytes, and optimize hemodynamics – Always save 10-20 mL urine for urinalysis and FENa before giving fluids and diiuretics.
– Discontinuation of offending agents if possible.
– Attempt diuresis with high-dose loop diuretics. Dialysis or continuous hemodiafiltration (alternative to dialysis) for symptoms of uremia, fluid overload, or hyperkalemia.
– Specific treatments as indicated (i.e., nephrostomy for ureteral obstruction, plasma
exchange in TTP-HUS, steroids in rapidly progressive glomerulonephritis).
Clinical Course of ARF and Possible outcomes. Sudden, often reversible, interruption of renal function: prognosis depends on etiology
– Prerenal azotemia is reversible by definition
– Patients with oliguric ATN usually recover in 1 – 3 weeks
– Patients with contrast nephropathy recover in 3 – 7 days
Mortality in hospital-acquired ATN is still over 50% in surgical patients, due to multi-organ failure. Early response to a rise in creatinine may lead to prevention of ATN in the prerenal patient.
Renal Stone (Nephrolithiasis)
Causes of renal stone are numerous. Calcium oxalate stones are most common cause (65%), others include calcium phosphate uric acid. and stuvite (magnesium ammonium phosphate). Most often it occurs due to increased concentration of stone-forming material in urine either due to increased excretion or decreased urinary volume. Calcium-containing stones are due to increase urinay calcium/oxalate excretion (i.e., excess calcium absorption from bone in primary hyperparathyroidism (increased function of tiny glands in front part of neck). Uric acid stones are common in patients with gout. Struvite stones are usually due to urea-splitting organisms such as Proteus.
Incidence in US is less than 0.5%. lifetime incidence is 10 per cent. Male suffer more than females. Whites suffer more than blacks. Young to middle-aged adults are more prone. Paradoxically, high dietary calcium intake may decrease the risk of stones as it forms ligands with dietary oxalate and phosphate.
Renal stones are not to be mistaken for – Pyelonephritis, Papillary necrosis, Renal cell carcinoma, Back injury/spasm, Broken ribs, Herpes zoster, Dissecting aortic aneurysm, Biliary colic, Pancereatitis.
Signs and Symptoms of renal stone are – Severe, acute, colicky flank pain. Hematuria (stone in kidney) often with radiation to testicle or labia. Severe, acute urethral pain (stone passing through urethra). Nausea/vomiting are common. Dysuria, urgency, and frequency are less common. Obstruction of ureter may result in anuria or acute renal failure in patients with a single functioning kidney : rarely, bilateral ureteral obstruction may occur. Fever/chills and other constitutional symptoms if infection complicates the picture. CVA tenderness (Heart and blood vessel causes).
Diagnosis of renal stone include – A history of flank pain and the presence of microscopic or gross hematuria mandates imaging studies (blood ). Urinalysis, urine pH, and urine culture. MRI PAT SCAN Spiral CT and abdominal films may be diagnostic if the stone is radio-opaque (Ca+ + – containing stones, struvite, cysteine). Ultrasound and intravenous pyelogram for radiolucent stones, to better localize stones, and to detect obstruction. Search for etiology of stone, especially if recurrent,
– Strain urine and send stone to the lab if possible
– 24-hour urine collection for volume, pH. calcium, citrate, oxalate, phosphorus, uric acid. ammonium, magnesium
– Serum chemistries and parathyroid hormone evaluation
– Consider many systemic diseases that can contribute to development of urolithiasis
(e.g., gout. enzyme deficiencies, malignancy, sarcoidosis).
Treatment of nephrolithiasis is as follows. Surgically active stone disease (passing a stone) is treated with hydration and analgesics (NSAIDs, narcotics). Stones too large to pass require external shock wave lithotripsy, cystoscopic or ureteroscopic laser lithotripsy, stenting, basker retrieval, or urolithetomy. Admit to hospital if patient is unable to keep fluids down or pain is not adequately managed. Treat infection if present. Prevention via increased water more than 3L/day). Directed treatment depending on type of stone
– Limit sodium intake and thiazide diuretics for, Ca + + – containing stones with hypercalciuria.
– Dietary oxalate reduction if hyperoxaluria
– Alkalinize urine and allopurinol if hyperuricosuria Penicillamine for cystinuria.
To mention Prognosis and Clinical Course of renal stone, 90 per cent of stones less than 4 mm pass spontaneously. Less than 10% of stones, over 6 mm pass spontaneously. Prognosis depends on the type of stone and the primary cause for stone formation. Recurrence is very common – 14 per cent at one year after first stone and 75 per cent at 20 years. All patients should be counseled to increase water intake after passing their first stone.
I would like to apologise for unavoidably using some medical terms, which I am sure may bore you. Ignoring these unfamiliar technical usage, may I present some take-home-messages in a simple and digestable language:-
– kidney diseases are not uncommon in the community
– kidneys are precious for every person
– dialysis is costly and not accessible to all
– kidney transplants are not easy procedures for damaged kidneys
– donors’ kidneys are often rejected by the recepient, unless donor is a close relative,
immediate brother or sister or a twin.
– early diagnosis is crucial.
– Consult immediately your doctor for even trivial urinary complaints. Your doctor will screen and refer appropriate patient to a nephrologist or urologist for further
– Live a healthy life style with copious drinks; avoid reno-toxics including diets.
– Avoid smoking, betel squids, moderete alcohol
– Last but not the least, avoid consuming Danyinthee for God’s sake.