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Historia De La Penicilina: Más Allá De Los Héroes, Una Construcción Social

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Historia De La Penicilina: Más Allá De Los Héroes, Una Construcción Social HISTORIA DE LA MEDICINA Historia de la penicilina: más allá de los héroes, una construcción social Nicolás Giraldo-Hoyos1,2 RESUMEN El hecho científico conocido como “penicilina” se ha considerado tradicionalmente como el producto del ingenio de Alexander Fleming, ganador del Premio Nobel por descubrir esta “droga milagrosa”. Apartándose de esta idea popular, se hace necesario resaltar el desarrollo de la penicilina como un constructo social, producto del trabajo invaluable de varios científi- cos, sumado a un contexto social excepcional que motivó la voluntad política y el apoyo de la industria farmacéutica; en ausencia de cualquiera de estos, la penicilina no sería lo que sig- nifica hoy para nosotros o, simplemente, no existiría en el arsenal terapéutico. Los conceptos epistemológicos de “estilo de pensamiento” y “colectivo de pensamiento” como fundamentos en la construcción del conocimiento, presentes en la obra epistemológica de Ludwick Fleck, apoyan la conclusión, a partir del recuento histórico, de la necesidad de apartarnos de la penicilina como el producto de un descubrimiento de un único héroe, para verla como una construcción social, que además es un ejemplo clásico de serendipia. La penicilina, además, tiene otras facetas menos conocidas históricamente como el uso de ella de manera cruda, producida y usada por médicos generales, o la búsqueda de información para su producción durante la segunda guerra mundial; estas se abordan en este breve recuento histórico. PALABRAS CLAVE Historia; Penicilinas; Penicillium; Segunda Guerra Mundial SUMMARY History of penicillin: Beyond heroes, a social construction The scientific breakthroug we know as “penicillin”, has been traditionally considered as the re- sult of the genius of Alexander Fleming, awarded with the Nobel Prize for the discovery of the 1 Médico de la Universidad de Caldas, Manizales, Colombia. 2 Miembro del Grupo de Resistencia Antibiótica de Manizales (GRAM), Manizales, Colombia. Correspondencia: Nicolás Giraldo-Hoyos; [email protected] Recibido: abril 20 de 2020 Aceptado: julio 20 de 2020 Cómo citar: Giraldo Hoyos N. Historia de la penicilina: más allá de los héroes, una construcción social. Iatreia. 2021 Abr-Jun;34(2):172-79. DOI 10.17533/udea.iatreia.79. 172 IATREIAIATREIA Vol 34(2) Vol 172-179 34(2) abril-junio 2021 “miracle drug”. Standing aside from this popular idea, Luego la cuestión era curar al enfermo, para lo que it is important to highlight the development of penici- debía ampliarse el entendimiento de la interacción llin as a social construct and the product of the invalua- entre humanos y patógenos. Paul Ehrlich introdujo ble work of several scientists, in addition to an excep- alrededor de 1908 el concepto de “bala mágica”, en- tional social framework that raised the political desire tendida como una sustancia que, introducida en el and the pharmaceutical industry support; without any organismo, mataría al patógeno sin dañar las células of these, penicillin wouldn’t even have the meaning it del paciente (4). Su trabajo con los arsenicales Salvar- has today, or it wouldn’t even exist. The epistemologi- sán y Neosalvarsán concluyó que eran considerable- cal concepts of “style of thinking” and “collectivity of mente tóxicos y no fueron balas mágicas, pero creó thought” as basis in the construction of knowledge, pre- la esperanza de encontrar la anhelada sustancia (5,6). sent in Ludwick Fleck’s epistemological work, support Lo más cercano a bala mágica apareció como una the conclusion, based the historical account, about serendipia en el laboratorio de Alexander Fleming, the need of standing aside from the idea of penicillin pero llevarla a las farmacias y hospitales requirió del as the discovery of a single hero, and considering it a trabajo de muchas personas, sobre la base de concep- social construction instead, and a classical example of tos predecesores. Este trabajo relatará la historia de serendipity. Other aspects less known about penicillin cómo se construyó la penicilina como la conocemos history, such as the use of crude penicillin by general hoy, resaltándola como una construcción social y no practitioners, or the seeking of information about how la hazaña de un único héroe científico. to produce it during World War II, which are addressed in this brief historical account. ANTAGONISMO MICROBIANO La terapéutica antimicrobiana se basa en el antago- KEY WORDS nismo microbiano, fenómeno estudiado simultánea- History; Penicillins; Penicillium; World War II mente en varios países europeos. Vincenzo Tiberio, médico italiano, notó que los mohos podían eliminar bacterias del agua por medio de sustancias solubles, cada una con diferente potencia antimicrobiana (7,8). INTRODUCCIÓN En Francia, Gabriel Roux, afamado micólogo, notó Hacia el año 1859 Louis Pasteur estableció la teoría que las esporas de hongos no contaminaban el agua microbiana de la enfermedad (1), cambiando el para- de grifos o fuentes, pero sí podían cultivarse en agua digma de las enfermedades infecciosas desde la multi- destilada; propuso a Ernest Duchesne, estudiante de causalidad hacia una perspectiva unicausal, es decir, medicina y alumno suyo, investigar este fenómeno un microorganismo se asocia con una enfermedad (9,10). Duchesne demostró en 1897 que Penicillium particular. Esto impulsó múltiples descubrimientos de glaucum inhibía a Salmonella Typhi en animales de microorganismos patógenos por varios científicos, en- experimentación, y que la victoria de mohos o bac- tre ellos Robert Koch, quien formalizó la teoría micro- terias dependía de factores físicos medioambientales, biana de la enfermedad por medio de sus postulados, pero no aisló la sustancia bactericida (9,11). construidos siguiendo el trabajo de Jakob Henle (2). Se Selman Waksman, microbiólogo estadounidense acu- estableció un nuevo “estilo de pensamiento” en térmi- ñó el término “antibiótico”, refiriendo que el primer nos de la obra epistemológica de Ludwick Fleck, defi- uso de la palabra “antibiosis” lo hizo el micólogo fran- nido como las presuposiciones acordes con un estilo, cés Paul Vuillemin, citando sus palabras: “Una criatu- con el que un “colectivo de pensamiento” construye ra destruyendo la vida de otra para sostener la propia, un saber; es decir, les da un observar sistemático de un una en oposición sin restricciones contra la vida del fenómeno y métodos propios para la construcción del otro” (12); Vuillemin usó la palabra “antibiose” ini- conocimiento. El “colectivo de pensamiento” es la uni- cialmente como antónimo de simbiosis (13). Pasteur dad social de la comunidad científica que se identifica ya había notado la acción de P. glaucum al conocer con este estilo de pensamiento (3). que el hongo había sido usado durante siglos por los 173 IATREIA Vol 34(2) abril-junio 2021 habitantes de las estepas rusas y las llanuras de Gran refiriéndose al filtrado del caldo de cultivo (22), indi- Bretaña para curar heridas adquiridas en el suelo (9). cando el origen de la penicilina a partir del Penici- El mismo hongo tuvo éxito para tratar los abscesos en llium, así como la digitalina era originaria de la planta experimentos de Lister hacia 1884 (9,10) y del médico Digitalis (24). J. R. Mose (14). La palabra serendipia describe un “hallazgo valioso que se produce de manera accidental o casual” (25). Este término tiene origen en el relato persa Los tres SERENDIPIA EN EL LABORATORIO príncipes de Serendip, conocidos por su sagacidad al La penicilina no fue la primera sustancia antibiótica hacer hallazgos afortunados y deducciones acertadas conocida. La Piocianasa, originada del bacilo pio- (26). Fue una serendipia que, precisamente, este hon- ciánico, resultó muy tóxica para el uso sistémico y go haya sido el que infectó sus cultivos (24). Esto no se limitó a la acción tópica hasta luego desaparecer fue solo un momento de suerte, pues queda claro con (15). Desde su reconocimiento como entidad clínica qué rigurosidad se estudió la sustancia, además, como en Europa, se usaron diferentes tratamientos contra resalta Orlando Mejía Rivera en su obra El desorden de la sífilis, uno de los más famosos fue el “Unguentum Fleming y otros ensayos patobiográficos, no solo hace Saracenicum” que contenía óxido amarillo de plomo falta suerte para percibir un hallazgo inesperado afor- y gran cantidad de mercurio. Se evidenció la efecti- tunado, sino también la sagacidad para interpretarlo vidad del último en el tratamiento; incluso Paracelso y orientarlo adecuadamente, dando razón a Louis lo usó en píldoras, pero su toxicidad hizo necesario Pasteur al decir: “la suerte solo favorece a las mentes buscar otras alternativas, entre las que se encontra- preparadas” (26). Fleming falló al intentar aislar el prin- ban sustancias de origen vegetal como el Guayaco, la cipio activo presente en el caldo de cultivo (22). “raíz china” y la “sarsaparilla” (16). En 1907 se sinteti- La penicilina no llegó al mercado hasta la década de zó el Salvarsán y luego en 1914 el Neosalvarsán, estos 1940, pero existen registros de usos tempranos del se volvieron el tratamiento de elección para la sífilis caldo de cultivo en infecciones oftálmicas y cutáneas hasta ser reemplazados por la penicilina (15,17,18). de forma tópica entre 1930 y 1931 por George Paine, Ninguno fue la “bala mágica” al no cumplir con los incluso Fleming, la usó para tratar conjuntivitis, abs- criterios propuestos por Ehrlich, especialmente, la cesos, quemaduras y úlceras (27). inocuidad para el hospedero, por lo que debía conti- nuarse la búsqueda de la droga milagrosa. En septiembre de 1928, un médico escoces llamado EL EQUIPO DE OXFORD Alexander Fleming regresaba de sus vacaciones a su laboratorio en el Hospital St. Mary de Londres (19). No Al iniciar la Segunda Guerra Mundial, Howard Florey hay claridad si fue Fleming o su asistente, Merlin Pri- y Ernst Boris Chain, del equipo de investigadores de la ce, el primero en ver la inusual contaminación (20). Universidad de Oxford (19), iniciaron esfuerzos para En cualquier caso, Fleming había dejado varias cajas perfeccionar la sustancia descubierta por Fleming de Petri con cultivos de Staphylococcus aureus y so- (3).
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