The role of procalcitonin as a guide for the diagnosis, prognosis, and decision of antibiotic therapy for lower respiratory tract infections

Abstract

Objectives: To assess the value of PCT as a rapid and sensitive marker for diagnosis, prognosis, and therapy of lower respiratory tract bacterial infections necessitating antimicrobial treatment and comparing this marker with other markers of infections including C-reactive protein (CRP) and total white-blood cell counts (WBCs).Patients and methods: Sixty Patients were enrolled in the study, they were subjected to complete history taking, physical examination, laboratory investigations including complete blood count, blood gases, blood chemistry, bacteriological culture for sputum and blood, serology for atypicals, and PCR for respiratory viruses, serum C-reactive protein (CRP) and PCT levels were measured. The patients were divided into two groups, group 1 included 26 patients who were culture negative for bacterial infection and group 2 included 34 patients who were culture positive. Group 2 patients were given antibiotic therapy according to the culture sensitivity.Result: The results revealed that, there was no significant difference between group 1 and group 2 patients as regards age, sex, clinical manifestations, final diagnosis, white blood cell counts, blood gases, number of admitted patients, intensive care unit admission and length of hospital stay. A significant increase of PCT and CRP levels was detected in group 2 compared to group 1 at initial Open access under CC BY-NC-ND license.diagnosis. At cutoff value >0.5 ng/ml, PCT gave a sensitivity of 94.1%, specificity of 88.4%, positive predictive value (PPV) of 91.4%, negative predictive value (NPV) of 92% and diagnostic efficiency of 91.6% for diagnosis of respiratory tract bacterial infections. However, at a cutoff value >8 mg/L, CRP gave a sensitivity of 85.2%, specificity of 76.9%, PPV of 82.8%, NPV of 80% and diagnostic efficiency of 81.7%. After antibiotic therapy PCT and CRP levels dropped in group 2 patients as compared to their pre-treatment levels.Conclusion: Serum PCT level could be used as a novel marker of lower respiratory tract bacterial infections for diagnosis, prognosis and follow up of therapy. This reduces side-effects of an unnecessary antibiotic use, lowers costs, and in the long-term, leads to diminishing drug resistance.

Assessment of the Immune Response of Clinically Infected Calves to Cryptosporidium parvum Infection

“…The significant changes in APPs and CYTs levels in C. parvum-diseased calves versus those in recovered ones indicated that these makers might be used to estimate treatment success. These markers have been used in both humans and animals for diagnosis, prognosis, and treatment monitoring [7,11,[46][47][48]. There have been several reports of serum OS in sick animals [49,50].…”

Procalcitonin Monitoring as a Guide for Antimicrobial Therapy: A Review of Current Literature

“…11,12 PCT demonstrates a mean sensitivity of 77% and a specificity of 79% for the diagnosis of sepsis, and a sensitivity of 94.1% and a specificity of 88.4% for the diagnosis of LRTIs. 12,13 The negative predictive value for PCT was shown to bẽ 89-94% for ruling out both sepsis and LRTIs. 14,15 However, the 2016 Surviving Sepsis Campaign and the 2016 Infectious Diseases Society of America (IDSA) guidelines for the management of hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) recommend against utilizing PCT to decide whether or not to initiate antibiotic therapy (strong recommendation, moderate-quality evidence).…”

“…For the diagnosis of sepsis and LRTIs, in conjunction with other diagnostic tools and clinical examination, PCT levels were shown to be more sensitive and more specific than other biomarkers, including IL‐6, CRP, and lactate . PCT demonstrates a mean sensitivity of 77% and a specificity of 79% for the diagnosis of sepsis, and a sensitivity of 94.1% and a specificity of 88.4% for the diagnosis of LRTIs .…”

Elevated PCT at ICU discharge predicts poor prognosis in patients with severe traumatic brain injury: a retrospective cohort study

“…8 Studies have confirmed that for diagnosing sepsis and lower respiratory tract infections, PCT levels combined with other diagnostic tools and clinical examinations are more sensitive and specific compared with other biomarkers (including interleukin (IL)-6, CRP, and lactate). [9][10][11] CRP is secreted 4 to 6 hours after stimulation by bacterial infection and peaks within the following 36 hours; however, serum PCT levels can persist for long periods, providing an opportunity to track changes in the disease's clinical manifestations. Thus, PCT can be used to predict the inflammatory states of critically ill patients.…”