The possible effects of iron loss from bloodletting on mortality from pneumonia in the nineteenth century
Historical / methodology analysis published in J Clin Epidemiol (2021)
Abstract
OBJECTIVE: To estimate iron losses and disease severity following 19th century bloodletting in patients with pneumonia. STUDY DESIGN AND SETTING: Benefits of bloodletting in pneumonia patients were contested during the 19th century. Although large blood volumes during infection were removed there was no systematic data collection assessing efficacy and knowledge of iron composition of blood was rudimentary. This observational analysis of historical data quantifies iron losses in pneumonia cases in relation to disease severity. RESULTS: Based on one detailed case series average blood volume removed for survivors was 830 mL (range 114-2272 mL), and mean recovery times were shorter in patients bled within 2 days of illness (P < 0.001). Average iron removed was 446 mg with phlebotomy done ≤2 days of illness presentation and 347 mg after >2 days of illness (P = 0.012). Across several European hospitals average case fatality in pneumonia patients receiving phlebotomy was higher than in those treated without phlebotomy (19.9% vs. 12.8%, OR 1.55, 95% CI 1.38-1.74, P < 0.001). CONCLUSION: Variable efficacy for bloodletting could at least in part be explained by altered iron status.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Resumen
Quantitative analysis of 19th-century pneumonia bloodletting showing average 446 mg iron removed per phlebotomy and 19.9% case fatality versus 12.8% without phlebotomy.
Por qué esto importa para la hirudoterapia
Esta revisión histórica analiza las pérdidas de hierro resultantes de la flebotomía del siglo XIX en pacientes con neumonía, encontrando que el volumen sanguíneo promedio extraído era significativo y que la letalidad fue mayor en los pacientes que recibieron flebotomía en comparación con aquellos que no la recibieron. El estudio examina las prácticas históricas de extracción sanguínea y sus consecuencias fisiológicas, centrándose específicamente en la flebotomía. Su relevancia para el ámbito de la ASH es estrictamente indirecta, ya que el resumen trata exclusivamente sobre la flebotomía y nunca menciona sanguijuelas ni hirudoterapia. La conexión se limita únicamente al concepto histórico compartido de la terapéutica de extracción sanguínea, y no puede establecerse un vínculo directo con las sanguijuelas a partir del resumen proporcionado.
Citación
The possible effects of iron loss from bloodletting on mortality from pneumonia in the nineteenth century.
Brabin B et al. · Journal of clinical epidemiology, 2021
Contexto clínico relacionado
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Añadido a la biblioteca ASH: May 27, 2026 · Última actualización del sitio: 18 de junio de 2026