ABSTRACT
BACKGROUND/AIMS: The diagnostic yield of fecal leukocyte and stool cultures is unsatisfactory in patients with acute diarrhea. This study was performed to evaluate the clinical significance of the fecal lactoferrin test and fecal multiplex polymerase chain reaction (PCR) in patients with acute diarrhea. METHODS: Clinical parameters and laboratory findings, including fecal leukocytes, fecal lactoferrin, stool cultures and stool multiplex PCR for bacteria and viruses, were evaluated prospectively for patients who were hospitalized due to acute diarrhea. RESULTS: A total of 54 patients were included (male, 23; median age, 42.5 years). Fecal leukocytes and fecal lactoferrin were positive in 33 (61.1%) and 14 (25.4%) patients, respectively. Among the 31 patients who were available for fecal pathogen evaluation, fecal multiplex PCR detected bacterial pathogens in 21 patients, whereas conventional stool cultures were positive in only one patient (67.7% vs 3.2%, p=0.000). Positive fecal lactoferrin was associated with presence of moderate to severe dehydration and detection of bacterial pathogens by multiplex PCR (21.4% vs 2.5%, p=0.049; 100% vs 56.5%, p=0.032, respectively). CONCLUSIONS: Fecal lactoferrin is a useful marker for more severe dehydration and bacterial etiology in patients with acute diarrhea. Fecal multiplex PCR can detect more causative organisms than conventional stool cultures in patients with acute diarrhea.
Subject(s)
Adult , Female , Humans , Male , Biomarkers/analysis , Dehydration/enzymology , Diarrhea/complications , Feces/enzymology , Lactoferrin/analysis , Multiplex Polymerase Chain Reaction/statistics & numerical data , Prospective StudiesABSTRACT
INTRODUCCIÓN. Los leucocitos fecales son utilizados para identificar diarrea invasiva y decidir el uso de antibióticos. Se conoce poco sobre su utilidad en hospitales de países en desarrollo con procesos de laboratorio eficientes. Buscamos evaluar el rendimiento diagnóstico de la prueba en menores de 5 años con diarrea aguda. MATERIAL Y MÉTODOS. Estudio retrospectivo de registros clínicos y de laboratorio en el Hospital de Emergencias Pediátricas, Lima, Perú. Se evaluó los casos a los que se había solicitado sistemática e independientemente leucocitos fecales y coprocultivo. Se calculó sensibilidad, especificidad, valores predictivos, cocientes de probabilidad (CP) y la curva de características operativas del receptor (ROC). RESULTADOS. De 1,804 muestras fecales, 901 (49,9%) fueron positivos para uno o más enteropatógenos bacterianos. La sensibilidad (S), especificidad (E), y el CP positivo variaron para los diferentes umbrales: más de 5 leucocitos por campo (S: 93.2%, E: 21.9%, CP: 1.9), más de 20 (S: 88.4%, E: 34.8%, CP: 1.35), más de 50 (S: 74.9%, E: 56.7%, CP: 1.73), y más de 100 (S: 60.7%, E: 71.9%, CP: 2.17). El área bajo la curva ROC fue 0.69 (IC 95%: 0.67-0.72). CONCLUSIONES. El rendimiento de la prueba es sub-óptimo y continuar su uso rutinario en la práctica clínica no parece justificado, pues promueve el abuso de antibióticos y por otro lado aumenta el riesgo de pasar por alto pacientes con diarrea invasiva. Se necesita estudiar el rendimiento diagnóstico de datos epidemiológicos y clínicos combinados con leucocitos fecales o lactoferrina fecal, para identificar una aproximación más eficiente.
INTRODUCTION. Fecal leukocytes are widely used to identify invasive diarrhea and to make then the decision of prescribing or not antibiotics. This test has been hardly assessed in small hospitals of developing countries with efficient laboratory processes. We aimed to assess the diagnostic performance of different thresholds of fecal leukocytes in children under-five with acute diarrhea. MATERIAL AND METHODS. Retrospective study of clinical and laboratory records in the Pediatric Emergency Hospital, Lima, Peru. All cases with a stool culture and fecal leukocytes independently and systematically performed were studied. Sensitivity, specificity, predictive values, likelihood ratios (LR), and receiver operating characteristics (ROC) curves were calculated. RESULTS. Out of 1,804 stool samples assessed, 901 (49,9%) were positive for one or more bacterial entheropathogens. Sensitivity (Sn), specificity (Sp), and positive LR varied for different thresholds: more than 5 (S: 93.2%, Sp: 21.9%, LR+:), more than 20 (Sn: %, Sp: %, +LR: ), more than 50 (Sn: 74.9%, Sp: 56.7%, +LR: 1.73), and more than 100 fecal leukocytes per high power field (Sn: 60.7%, Sp: 71.9%, LR+: 2.17). The general area under the ROC curve was 0.69 (CI 95%: 0.67-0.72). CONCLUSIONS. Diagnostic performance of fecal leukocytes is suboptimal and may not warrant its continued use in developing settings, as it promotes antibiotic abuse, and on the other hand increases the risk of overlooking patients with invasive diarrhea who may benefit from antibiotic treatment. Combination of epidemiological and clinical data with either fecal leukocytes or fecal lactoferrin may provide a more efficient approach.
Subject(s)
Child , Humans , Bacterial Infections/diagnosis , Diarrhea/etiology , Feces/cytology , Leukocytes , Acute Disease , Developing Countries , Diarrhea/microbiology , Likelihood Functions , Predictive Value of Tests , ROC Curve , Retrospective Studies , Sensitivity and SpecificityABSTRACT
BACKGROUND: Most episodes of acute diarrhea are self-limiting. Most patients require neither a stool culture nor antibiotic therapy. This study was designed to investigate the predictors of a stool-culture positivity and indicators for antibiotic therapy in acute infectious diarrheal patients. METHODS: Medical records of 139 adult cases were retrospectively reviewed during the 12 months between January 1999 and December 1999. We used the Chisquare-test to analyze the data for statistical significance. RESULTS: Fecal leukocytes were examined in 104 cases; 30 tested positive (28.8%). Eighty-five stool cultures were taken, and 24 yielded enteric pathogens, such as Salmonella, Shigella, V. Cholera and V. Parahaemolyticus. Cultures from patients treated between August and October, with fever above 37.6degrees C, or with symptoms of abdominal pain had higher yields(44.2% vs 11.9%, p=0.001, correlation coefficient=0.359; 36.8% vs 10.7%, p=0.012, correlation coefficient=0.273;, 38.1% vs 18.6%, p=0.046, correlation coefficient=0.216 ; respectively) and when combined with fecal leukocytes had a sensitivity of 100% and a specificity of 90.1-95.1%. CONCLUSION: The primary variables (season, fever, and abdominal pain) were excellent predictors of stool culture positivity and indicators for antibiotic therapy, especially when combined with fecal leukocytes