(Fig.1)The tongue was large, pale and had very characteristic deep and prominent teeth impressions along the edges

During a period of 15 years from 1975, in over 640 uraemic patients of age group 20-60 years, this very characteristic abnormality in their tongue was observed in 512 (80%) cases. This finding had not been reported by anyone else so far. There were 504 patients Chronic renal failure of varied aetiology including chronic glomerulonephritis, diabetic nephropathy, chronic interstitial nephritis, hereditary nephritis etc.(Table – 1) and 8 patients with Acute renal failure – 4 following poisonous snake envenomation, 2 with Weil’s disease and 2 patients with rapidly progressive crescentic glomerulonephritis (Table – 2). These patients were studied in detail regarding the basic renal disease, renal function, pH of saliva, urea content of saliva, oral bacterial flora and macroscopic and microscopic appearance of the tongue. As controls, the tongue of normal individuals of nephritic patients and patients with severe anaemia and anasarca were studied.

The pH of saliva was acidic in 93% of cases, while it was alkaline in the controls. The urea level of saliva was high with an average of 75mg% as compared to normal of less than 15mg% in all the cases. The oral bacterial flora was “mixed” in 55%, “streptococcal” in 35% and “sterile” in the rest. In 92% of cases with uraemia, the tongue was large, macroglossic, pale and had very characteristic, striking and prominent impressions of the teeth all around the edges (Fig.1). There was no direct correlation with the degree of uraemia and the development of the abnormality in the tongue. In 8-10% of the cases, the abnormal tongue was seen in early uraemic state, when the blood urea was between 50-100mg% while in the rest, the blood urea values were over 100mg%. Teeth impression alone without the features like marked pallor and macroglossia was seen in 2% of normal controls studied.[3,4]

Fig 2 Histopathology of tongue showing acanthosis	Fig 3 Histopathology of tongue showing loss of papillae and marked sub-epithelial oedema

Microscopically (Fig.2&3), the tongue tissue showed parakeratosis, acanthosis, loss of papillae and marked sub-epithelial oedema. The deeper tissues were normal. None of these changes were seen in the control groups.[5] 

The changes observed in the tongue in uraemia could very well be due to the acidic pH of saliva and or due to the abnormal oral bacterial flora as well as the high urea content of the saliva in the uraemic patients. On follow up, in many patients, the abnormality of the tongue was found to disappear gradually and regain the normal state when the patients were started on Dialysis or on recovery from the uraemic state or soon after renal transplantation.

It could be postulated that it is the “uraemic milieu” that has produced the changes in the tongue and when it is corrected by dialysis or transplantation or by recovery from acute renal failure, the tongue regained its normal colour, size and shape. With the clinical and histopathological correlations, I feel that this original observation in uraemic patients should be designated as the “Tongue Sign of Uraemia”.

Table – 1: Split-up of CRF Cases having Tongue Sign

Table II – Split-up of ARF Cases having Tongue Sign

References:

1) Barry M. Brenner, Karl Skoreski and Jacob Green. ‘Chronic Renal Failure’ in Harrisons Principles of Internal Medicine, 15th edition, Volume 2, Edited by Eugene Braunwald, Anthony S, Fauci, Dennis L.Kasper, Stephan L.Hauser, Dan L.Longo and J.Larry Jameson, New York, Mc Graw Hill, 2001, p.1553.

2) Richard Amerling and Nathan W.Levin. ‘Uremia’ in Massery’s and Glassock’s Text Book of Nephrology – 4th Edition, edited by Shawl G Massery and Richard J.Glassock, Philadelphia, Lippincott Williams and Wilkins, 2001, p.559.

3) Thomas Mathew M, Pradeep Kumar, Rajaratnam K, Rajalakshmy PC and Leelamma Jose. “The Tongue Sign of CRF – A New Clinical Sign in CRF” (Abstract) JAPI, January 1984.

4) Thomas Mathew M. “In Pursuit of an Original Observation”. Indian Journal of Nephrology, Vol.4 (Suppl.20) 3; 1994.

5) Thomas Mathew M, Rajaratnam K, Rajalakshmy PC and Leelamma Jose. “The Tongue Sign – Further Clinical and Histopathological Evidence”, JAPI, 34: 52, 1986.

© Copyright of articles belongs to the respective authors unless otherwise specified.Verbatim copying, redistribution and storage of this article permitted provided no restrictions are imposed on the access and a hyperlink to the original article in Calicut Medical Journal maintained. All opinion stated are exclusively that of the author(s).
Calicut Medical Journal upholds the policy of Open Access to Scientific literature.