Nancelle Grace G. Dumlao
1. WHEN IS BIPOSY INDICATED IN CLIENTS SUSPECTED OF GN?
2. WHAT IS THE BASIS OF DIETARY REGIMEN AMONG GN CLIENTS? WHAT ARE THE RESTRICTIONS?
PLEASE PROVIDE STUDIES THAT SUPPORT YOUR RESPONSES.
ANSWER 1: 1. WHEN IS BIPOSY INDICATED IN CLIENTS SUSPECTED OF GN?
Glomerulonephritis (GN) is a kidney disease that presents in many different ways and accurate diagnosis can be difficult. Certain signs and symptoms may suggest GN but normally it is discovered when a urine urinalysis is not normal (with RBC or casts could mean glomerular damage; WBC means infection, increased protein du e to nephron damage). GN may be also be diagnosed using history, examination, blood tests (creatinine and urea) and even hard-to-control high blood pressure, but a definitive diagnosis can be achieved using renal biopsy.
GN is one of the major causes of CRF and since the progression of GN is such that the disease is already established before it becomes apparent, the kidneys of CRF patients may become small smooth kidneys (nephrosclerosis). At this point, renal biopsy in no longer advisable since it could be more dangerous to the patient. Hence, many nephrologist order renal biopsy only for patients who will benefit in specific treatments and when knowing the prognosis is vital. For instance, those patients with good prognosis such as those with mild hematura and low level proteinuria (less than 2g/day) with no renal impairment nor hypertension, they may be managed with regular check-ups. However, if the patient has increased proteinuria, hypertension or there is deterioration in kidney function, then renal biopsy is strongly indicated (Mason, 1994).
In a review of several studies done by Cohen and Brown (2003), they explored the significance of microscopic hematuria as initial warning sign for underlying diseases such as glomrulonephritis, other kidney disease, cystitis and other illnesses. They also reviewed previous studies on when microscopic hematuria should be followed by other diagnostic tests or when it may be safe to say that it is from benign causes (eg. Exercise, menstruation).
The study is quite long but let me just focus on its finding regarding the use of renal biopsy to further confirm the existence of glomerular damage.
Microscopic hematuria without proteinuria can either be of glomerular or nonglomerular (could involve the kidney and upper urinary tract) origin. If with microscopic hematuria, renal biopsy is not a routine follow-up test and thus, it cannot be determined if bleeding is from the glomeruli. In one study involving 157 men with microscopic hematuria whose cause could not be identified, the use of renal biopsy helped identified that bleeding in 16% of these men was due to a glomerular source. In another study with 165 patients, renal biopsy w as performed for each patient after renal imaging and cystoscopy. Renal biopsy was helpful in confirming that 87 patients had no abnormalities and 49 had IgA nephropathy.
Microscopic hematuria as mentioned above is the initial warning for glomerular bleeding. Further tests should be done to ascertain that renal insufficiency is present and they may be referred to a nephrologist for evaluation and possible renal biopsy. Referral should be immediate especially if second test of serum creatinine is abnormal or higher than the first result. However the indication for renal biopsy if microscopic hematuria is not accompanied by significant proteinuria or renal insufficiency is not supported due to the limited data available. But it was stressed that renal biopsy is indicate if the result could make a difference in the management or care of the illness.
Cohen,R.A., and Brown R.S. Microscopic Hematuria. The New England Journal of Medicine. June, 2003; volume 348:2330-2338.
Mason, P.D., Pusey, C.D. Fortnightly Review: Glomerulonephritis: diagnosis and treatment. BMJ. December, 1994, 309:1557-1563.
WHAT IS THE BASIS OF DIETARY REGIMEN AMONG GN CLIENTS? WHAT ARE THE RESTRICTIONS?
Several studies purport the low protein diet regimen for patients with kidney damage (GN and CKD among others). In the study below by Ideura, Shimazui, Morit, and Yoshimura in 2007, the authors further indicated that protein intake of more than 0.5 g/kg BW/day is no longer effective in controlling the further deterioration of chronic kidney failure.
However, it is still strongly recommended that patients with kidney problems should be referred to a kidney dietician for a diet regimen that is tailored to their current health condition so as to reduce the workload of their damaged kidneys.
In glomerulonephritis, there is serious kidney inflammation which may sometimes be triggered by circulating immune complexes (CIC) that may increase when large protein food molecules are released into the blood through the digestive tract. Hence, the limitation in protein intake is highly recommended.
The kidneys are susceptible to structural damages due to the various blood components being filtered on a daily basis. One cause of damage is the circulating immune complexes (CIC) which may increase when large protein food molecules are released into the blood through the digestive tract. Since the cause of the problem is the food that we take in, then this problem may also be resolved by controlling the kind of food that we eat. Through the years, there are numerous studies conducted to understand what foods may have damaging effects on the kidneys (Ferri, et al, 1993; Jackson, et al, 1992; Coppo, et al, 1991; Rostoker, et al, 1991). It has been proven that food-source of circulating immune complexes (CICs) contribute to some kidney problems. Glomerulonephritis, a serious kidney inflammation, is one disease which may sometimes be triggered by CICs which has food protein antigens. It has been suggested that recurring triad of signs and symptoms which are flank pain, blood or protein in urine are caused by “food allergy” until proven otherwise. Hence, diet which exclude antigenic material should be implemented (i.e. Alpha ENF which is a diet program offered to supplement those nutrients such as amino acids, Vit B, D, B12 and minerals such as calcium, magnesium, potassium, and zinc). . It is advisable that patients with kidney disease should eat low protein foods to decrease demands on deteriorating kidney function.
It is believed that proteins in general are high-risk food components in kidney disease and hydrolyzed proteins may have harmful effects. High protein foods that are excluded in the Alpha ENF list include gluten, the proteins in wheat, rye, barley and oats. Other high-protein foods are albumin from eggs and milk, muscle proteins from meat, globulin and casein from milk, and soy proteins. However, proteins from vegetables are better tolerated and maybe included in kidney diet.
A low protein diet and avoiding food-source of circulating immune complexes (CICs) may greatly control and enhance the function of the kidneys.
Protein Intake of More than 0.5 g/kg BW/Day Is not Effective in Suppressing the Progression of Chronic Renal Failure
By: Ideura T, Shimazui M, Morita H, Yoshimura A (2007)
This is a study was undertaken to identify how much protein should a patient with chronic renal failure (CRF) include in their diet. As mentioned above, it is well-known that protein restriction in the diet of CRF patients helps in controlling the progressive loss of kidney function, but there are no solid basis to support if this is really beneficial. In fact, there is still an issue regarding the amount of protein intake that could lead to positive outcome. Hence, this study was undertaken to identify the correct protein restriction that could translate to positive outcomes for patients with kidney disease. The sample included 121 patients with chronic glomerulonephritis (CGN) with serum creatinine level of 6mg/dl and they were further divided into six groups with corresponding amounts of protein restriction in their diet (e.g, 0.3 g/kg BW/day (0.3 g), 0.4, 0.5, 0.6, 0.7, and 0.8 g). The rate of decline in creatinine clearance were based on the whether kidney function deteriorates. Also, 24-hour urine sample was used to estimate the amount of protein intake as reflected by the appearance of urea nitrogen in the urine.
The study yielded significant information regarding the amount of protein intake that would have a beneficial effect on the kidney patient. It revealed that progression of renal dysfunction is suppressed for control groups with protein restriction in their diet of 0.5-, 0.4-, and 0.3-g groups. For those taking more than 0.6g of protein in their diet, there was no significant changes in the kidney dysfunction. They conclude that protein intake of more than 0.5g/kg BW/day is not effective in slowing down the deterioration of kidney function in CRF arising from chronic glomerulonephritis.
Ideura T, Shimazui M, Morita H, Yoshimura A. Protein Intake of More than 0.5 g/kg BW/Day Is not Effective in Suppressing the Progression of Chronic Renal Failure. Nutrition and Kidney Disease: A New Era. Contrib Nephrol. Basel, Karger, 2007, vol 155, pp 40-49 (DOI: 10.1159/000100995)
Ferri C; Puccini R; Longombardo G; Paleologo G; Migliorini P; Moriconi L; Pasero G; Cioni L. Low-antigen-content diet in the treatment of patients with IgA nephropathy. Nephrol Dial Transplant, 1993, 8:11, 1193-8.
Jackson S; Moldoveanu Z; Kirk KA; Julian BA; Patterson TF; Mullins AL; Jilling T; Mestecky J; Galla JH. IgA-containing immune complexes after challenge with food antigens in patients with IgA nephropathy. Clin Exp Immunol, 1992 Aug, 89:2, 315-20