Publikationsdatenbank

Investigations on the quantitative and qualitative protein excretion in urine of dogs with Severe Inflammatory Response Syndrome (SIRS) (2012)

Art

Hochschulschrift

Autor

Schaefer, Helen Leanne (WE 20)

Quelle

Berlin: Mensch und Buch Verlag, 2012 — 86 Seiten

ISBN: 978-3-86387-100-0

Sprache

Englisch

Verweise

URL (Volltext): https://refubium.fu-berlin.de/handle/fub188/8007

Kontakt

Klein- und Heimtierklinik

Oertzenweg 19 b
14163 Berlin
+49 30 838 62422
kleintierklinik@vetmed.fu-berlin.de

Abstract / Zusammenfassung

In response to severe injury or illness, inflammatory mediators initiate a systemic proinflammatory reaction, which is in turn attenuated or counteracted by the activation of modulating anti-inflammatory mechanisms. Severe inflammatory response syndrome (SIRS) is the state that occurs when an imbalance arises between pro- and anti-inflammatory responses. As a consequence of SIRS, endothelium cells are activated, vascular permeability is increased and vasodilatation, hypovolaemia, hypotension and tissue hypoxia occur. Increased renal filtration of plasma proteins is believed to result from these processes. The definition and diagnostic criteria for SIRS in humans, as developed in 1992, has recently been adapted by veterinarians for the recognition of SIRS in dogs. In the current study, 39 dogs with SIRS and 15 healthy dogs were examined for the presence, quantity and quality of proteins in their urine. Urine and blood samples were obtained from the diseased dogs on admission to a veterinary hospital as well as 24 (n=16) and 48 (n=24) hours thereafter, whenever possible. Urinalysis was conducted for total protein content and creatinine in order to calculate the urinary protein to creatinine ratio (UPC). Using ELISA, urinary albumin and RBP levels were also quantified and the ratios, albumin to urinary creatinine (UAC) and RBP to urinary creatinine (URBPC) were calculated. SDSPAGE was conducted for each dog to further identify the proteinuric pattern as indicative of low molecular weight (LMW) or middle molecular / high molecular weight (MMW/HMW) proteinuria. Furthermore, reference ranges for the level of urinary RBP and the URBPC were defined which could be used to help further establish reference values for future studies. This study showed that proteinuria is a common occurrence in dogs identified as having SIRS. Diseased dogs had significantly much higher levels for excretion of total urinary protein, UPC, albumin and RBP compared to the healthy dogs. 27 diseased dogs (69%) had a UPC > 0.5, 25 dogs (64%) had a UAC > 30 mg/g indicating microalbuminuria to overt proteinuria, whilst 36 dogs (92%) had a URBPC level above the defined upper limit of 33.3 μg/g. The incidence of abnormally high RBP in urine, regardless of whether or not UPC or albumin values were increased, indicated that an element of tubular malfunction was present in almost all diseased dogs. Whilst the UPC and UAC levels were significantly higher at admission than 48 hours later, this was not found for RBP, indicating that although glomerular proteinuria begins to subside within this time, tubular impairment may have a longer duration. The protein patterns obtained through visual inspection of SDS-PAGE showed great difference between the healthy and diseased dogs. The dogs with SIRS had a total of 11 different bands. Although a band in the range 60-70 kDa dominated, occurring in 36 dogs (92%), 58% of the total counted bands were in the LMW range whilst 42% were MMW/HMW. In the SDS-PAGE from the healthy dogs, 3 different bands were visible and only 45% of total counted bands were LMW. Through visual evaluation of the SDS-PAGE, all healthy dogs were deemed to have a physiological pattern. Of the diseased dogs, 11 (28%) exhibited an electrophoresis pattern indicative of tubular proteinuria, 18 (46%) had patterns suggesting mixed proteinuria, 2 (5%) had patterns indicating glomerular origins and 8 dogs (21%) were deemed to have physiological patterns. Previously reported gender-specific proteinuric differences were evident between entire healthy males and the remaining healthy dogs in this study. This was seen through the significantly higher UPC and higher number and intensity of specific LMW bands in urine from the healthy males compared with the other healthy dogs. Although 18 of 19 entire diseased dogs exhibited these specific bands, the generally higher incidence of LMW bands in urine of diseased dogs made an identification of gender specific patterns difficult. The higher level of proteinuria in the diseased dogs may also have masked possible genderspecific characteristics as no difference in UPC was observed between entire males and others. The search for differences in urinary protein excretion between survivors (n=26) and nonsurvivors (n=13) proved not remarkable as no significant differences were found between survivors and non-survivors, neither for proteinuria at admission nor on day 2. Although it appears that SIRS significantly influences renal protein filtration and reabsorption in dogs, correlations between the occurrence of acute proteinuria and mortality and proteinuria severity with mortality were not apparent. Of interest for future investigations is whether increasing or subsiding levels of proteinuria during the early stages of SIRS and in particular, individual trends in proteinuria of glomerular or tubular origin, could have implications for mortality prediction in dogs. Further investigation involving a larger patient collective would be valuable in the search for markers for the severity of a systemic inflammatory response and for evaluating prognosis in dogs with SIRS.