LETTERmmol l−1, p = 0.012) in comparison with predictor of diabetic complications is

limited.normal controls (2.31 ± 0.32 mmol l−1).LETTERSialic acid values were higher than thehealthy controls in the 38 normoalbumin-

V. Vijay, C. Snehalatha, A. Ramachand-uric, 33 microalbuminuric, and 37 pro-ran, M. Jayaramanteinuric diabetic patients (2.5 ± 0.66,Diabetes Research Centre, No. 4 Main2.95 + 1.06, 2.48 ± 0.68 mmol l−1,Road, Royapuram, Chennai 600 013.respectively) but a significantly higherIndiaSerum Sialic Acid in South Indian Type value was present only in the microal-

2 Diabetic Patients with Microvascular buminuric group (p , 0.05). We did notComplications observe a linear correlation between log

SSA and log A/C ratio. No correlationwas seen between log SSA and theIt is reported that serum sialic acid (SSA)

is increased in Type 2 diabetes mellitus presence of retinopathy (n = 40). SSA Referencesand shows a correlation to the presence values were similar in background, pre-

proliferative and proliferative retinopathyof micro-1–3 and macrovascular compli-cations.4 Pickup et al.5 reported in a pilot (2.4 ± 0.53 (n = 20); 2.4 ± 0.57 (n = 10) 1. Crook MA, Earle K, Morocutti A, Yip

J, Viberti G, Pickup JC. Serum sialicstudy that Asian diabetic patients had and 2.7 ± 0.8 mmol l−1 (n = 10), respect-ively. Most of the patients with micro-higher SSA levels compared to Caucasians acid, a risk factor for cardiovascular

disease, is increased in IDDM patientsmatched for age, sex, body mass, and albuminuria did not show retinopathicchanges. In the controls, there was noduration of diabetes. There are no reports with microalbuminuria and clinical

proteinuria. Diabetes Care 1994; 17:from patients in India. We therefore effect of gender on SSA values but asignificant positive correlation betweenmeasured SSA concentrations in Indian 305–310.

2. Chen J, Gall M, Yokoyama H, JensenType 2 patients with different degrees of SSA and systolic BP (p = 0.023). However,log transformed SSA in the patients didalbuminuria and also with and without JS, Deckert M, Parving H. Raised

sialic acid concentration in NIDDMretinopathy. One hundred and eight not show significant correlations withblood pressure, HbA1 or presence ofpatients (M:F 69 : 39) aged 55 ± 9.8 years patients with and without diabetic

nephropathy. Diabetes Care 1996;with duration of known diabetes 14 ± 6.2 retinopathy. Multiple linear regressionanalysis also failed to show an associationyears were studied. Twenty-three, healthy 19: 130–134.

3. Crook MA, Tutt P, Pickup JC. Elevatednon-diabetic controls of similar mean of SSA with any of these parameterstested in diabetic patients. Only a weakage and BMI were also tested. Albumin serum sialic acid concentration in

NIDDM and its relationship to bloodexcretion was measured in early morning association with BMI was noticed(p = 0.09, B = 0.016, SEB = 0.009).sample by a qualititative albumin test pressure and retinopathy. Diabetes

Care 1993; 16: 57–60.(TCA turbidity). Albumin/creatinine ratio SSA is a marker of acute phase glyco-proteins, as it is mainly derived from theirwas measured (A/C ratio normal 4. Pickup JC, Mattock MB, Crook MA,

Chusney GD, Burt D, Fitzgerald AP.,30 mg mg−1 creatinine) in subects with- metabolism, and may be increased indiabetic patients because of increasedout proteinuria. Urine albumin was meas- Serum sialic acid concentration and

coronary heart disease in NIDDM.ured by immunoturbidimetry on a Hitachi concentrations of acute phase proteinsfound even in the absence of compli-704 (Boehringer Mannheim, Germany). Diabetes Care 1995; 18: 1100–1103.

5. Pickup JC, Chana T, Mattock MB,Fasting blood samples were tested for cations.6–9 Our data contrast with thoseof Chen et al. who found progressivesialic acid, urea, creatinine, HbA1, serum Samuel A, Mather HM. Serum sialic

acid concentrations in Asian diabeticcholesterol, and triglycerides. SSA was increase in SSA with albuminuria inNIDDM patients.2 It is likely that in Asianestimated using an enzymatic kit patients in the UK. Diabetic Med

1996; 13: 284–285.(Boehringer Mannheim, Germany). The Indians, the acute phase proteins areincreased in the diabetic state itself, evenprocedure employs a coupled enzyme 6. Kannel WB, Agostino RB, Wilson

PWF, Belanger AJ, Gagnon DR. Dia-assay reaction involving neuraminidase, in the absence of any specific vascularcomplications and therefore strong corre-N-acetyl neuraminic acid aldolase and betes, fibrinogen and risk of cardio-

vascular disease; the Framinghampyruvate oxidase. H2O2 is formed and lation with vascular complications arelacking. It was shown by Pickup et al.estimated by a perioxidase dye system. experience. Am Heart J 1990; 120:

672–676.Between batch variation was less than that Asian Indian Type 2 DM patientswithout significant coronary heart disease7 %. A/C ratio of 30 to 300 m mg−1 was 7. McMillan DE. Increased levels of

acute phase serum proteins in dia-considered as microalbuminuria. Clinical had significantly higher SSA compared tomatched group of Caucasians.5 It is alsoproteinuria was defined as the presence betes. Metabolism 1989; 39: 1042–

1046.of proteinuria of $500 mg day−1 in 24 h interesting to note that the mean normalSSA value in the south Indians is higherurine collection. Blood pressure measure- 8. Crook M, Tutt P, Simpson H, Pickup

J. Serum sialic acid and acute phasement and opthalmoscopic tests for retino- than the values in Caucasians.In summary, our study showed that SSApathy were also done for all study subjects. proteins in type I and type II diabetes

mellitus. Clin Chim Acta 1993; 219:Using an upper cut-off value of was increased in Indian Asian Type 2 DMpatients, maximally in the presence of2.63 mmol l−1 for normal (mean ± SD in 131–138.

9. Rema M, Mohan V, Snehalatha C.the normal controls), only 46 out of the microalbuminuria. However, in view ofthe overlap between SSA values in the108 (42.6 %) of the diabetic patients had Acute phase serum proteins in dia-

betic retinopathy. Ind J Opthalmolhigh values of SSA. Diabetic patients as control and diabetic groups, with andwithout complications, its use as a specifica group had raised SSA (2.65 ± 0.82 1996; 44: 83–85.

176 CCC 0742–3071/98/020176–01$17.50 1998 John Wiley & Sons, Ltd. DIABETIC MEDICINE, 1998; 15: 176