The defense mechanisms of the urinary tract are attributed mainly to the innate immune system and the urinary tract urothelium which represent the first line of defense against invading pathogens and maintaining sterility of the urinary tract. There are only a few publications regarding cathelicidin (LL-37) and a urinary tract infection (UTI). This study was done to investigate the plasma and urine levels of human LL-37 in patients with UTI.
A case-control study was conducted at Omdurman Hospital, Sudan during the period from August 2014 to May 2017. The cases were patients with confirmed UTI and the controls were healthy volunteers without UTI. Sociodemographic and clinical data were obtained from each participant using questionnaires. Urine cultures and antimicrobial susceptibility were tested. Plasma and urine levels of LL-37 were determined using an enzyme-linked immunosorbent assay (ELISA) kit. SPSS (version 16.0) was used for analyses.
Cases and controls (87 in each arm) were matched according to their basic characteristics. Compared with controls, the median (inter-quartile) LL-37 level in plasma [2.100 (1.700–2.700) vs. 1.800 (1.000–2.200) ng/ml, P = 0.002] and in urine [0.900 (0.300–1.600) vs. 0.000 (0.000–1.000) ng/mg creatinine, P < 0.001] was significantly higher in cases. There was no significant difference in the median plasma [2.1 (1.7–2.9) vs. 2.000 (1.700–2.400) ng/ml, P = 0.561] and urine [0.850 (0.275–2.025) vs. 0.900 (0.250–1.350) ng/mg creatinine, P = 0.124]. The uropathogenic Escherichia coli (UPEC) was the predominant isolate, n = 38 (43.7%). LL-37 levels between the E. coli isolates and the other isolated organisms. There was no significant correlation between plasma and urine LL-37 levels (r = 0.221), even when the data of the cases were analyzed separately.
LL-37 is notably increased among patients with UTI compared with normal control subjects. Severity of UTI increases the levels of LL-37. The increased level was not only in the patient’s urine, but has also been observed in the patient’s plasma. Detection of increased levels of LL-37 could help to differentiate subjects with suspected UTI. Accordingly, LL-37 could act as a good marker for diagnosing UTIs.
Kumar V, Abbas AK, Aster JC. Robbins basic pathology: Elsevier health sciences; 2012.
Song J, Abraham S. Innate and adaptive immune responses in the urinary tract. Eur J Clin Investig. 2008;38(s2):21–8. CrossRef
Agerberth B, Charo J, Werr J, Olsson B, Idali F, Lindbom L, et al. The human antimicrobial and chemotactic peptides LL-37 and α-defensins are expressed by specific lymphocyte and monocyte populations. Blood. 2000;96(9):3086–93. PubMed
Nagaoka I, Hirota S, Niyonsaba F, Hirata M, Adachi Y, Tamura H, et al. Augmentation of the lipopolysaccharide-neutralizing activities of human cathelicidin CAP18/LL-37-derived antimicrobial peptides by replacement with hydrophobic and cationic amino acid residues. Clin Diagn Lab Immunol. 2002;9(5):972–82. PubMedPubMedCentral
Zanetti M. The role of cathelicidins in the innate host defenses of mammals. Curr Issues Mol Biol. 2005;7(2):179–96. PubMed
Övünç HD, Altun D, Hacıhamdioğlu B, Çekmez F, Aydemir G, Kul M, et al. The association between serum 25-Hydroxy vitamin D level and urine cathelicidin in children with a urinary tract infection. J Clin Res Pediatr Endocrinol. 2016;8:325. CrossRef
- The impact of cathelicidin, the human antimicrobial peptide LL-37 in urinary tract infections
Ibrahim H. Babikir
Elsir A. Abugroun
Naser Eldin Bilal
Abdullah Ali Alghasham
Elmuataz Elmansi Abdalla
- BioMed Central
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