Changes in urine substans P, vasoactive intestinal peptide and calcitonin-gene-related peptide levels in fifty-years old or older patients with urinary tract infection

Urinary tract infection is a commonly encountered disease leading to serious mortality and morbidity particularly in the elderly population. Hence early diagnosis and treatment is curicial. It was shown that; VIP, CGRP and SP, which are released from the sensory nerves, increased in inflammatory and infectious diseases. Increased peptide levels not only increases the local inflammatory response but also protect the organism against the pathogens. 67 patients between the ages of 50 and 90 years old, with the diagnosis of urinary tract infection from the outpatient or inpatient clinics of the Akdeniz University Faculty of Medicine Hospital, were included in the study. 37 healthy persons over 50 years-old age without any active complaint or any urinary tract infection symptoms were also included as the control group. Additionally, patients with the urinary tract infection symptoms (disurie, urgency) but without any microorganism cultivated in the urine cultures, were included in the study. All the patients were classified with respect to their sex, age (50-60 years old and 61-90 years of old age groups), presence of symptoms, presence of HT and DM history. Urine neuropeptide levels were determined in 15 improving patients after treatment, and they were compared with the previous results. There was a statistically significant increase in the CGRP levels of patient group with respect to the control group. Similar findings were previously reported in patients with severe systemic infection. VIP and SP levels were not significantly different between groups. CGRP levels were also increased in patients with sterile pyuria. Urinary samples were reexamined after appropriate antibiotic treatment in 15 patients. After-treatment SP levels showed a statistically significant decrease in the ceftriaxone treated group. This fact, considering the information in the literature, may be due to stimulation of sensory nerve endings by Ceftriaxone which depletes SP. SP, CGRP and VIP levels were consistently higher in female patients compared to male patients In conclusion, this study examined the urine neuropeptide levels of patients with urinary tract infection for the first time. Because we found that CGRP levels were increased in infection, it became a current issue that this peptide might have a role in pathogenesis. Furthermore increased levels of VIP, CGRP, SP observed in symptomatic patients suggest that symptoms of urinary tract infections may be treated with peptide antagonists. Further studies however required. Interestingly, in this study, it has been observed that cephalosporin group antibiotics may lead to sensory nerve activation in addition to their antibacterial properties. Key words: Urinary tract infections, substance P, vasoactive intestinal peptide, calcitonin gene related peptide.