A comparison of ancient parasites as seen from archeological contexts and early medical texts in China.

This paper integrates our knowledge from traditional Chinese medical texts and archeological findings to discuss parasitic loads in early China. Many studies have documented that several different species of eukaryotic endoparasites were present in early human populations throughout China. Nevertheless, comprehensive paleoparasitological records from China are patchy, largely due to taphonomic and environmental factors. An examination of early Chinese medical texts allows us to fill in some of the gaps and counteract apparent biases in the current archeoparasitological records. By integrating the findings of paleoparasitology with historic textual sources, we show that parasites have been affecting the lives of humans in China since ancient times. We discuss the presence and prevalence of three groups of parasites in ancient China: roundworm (Ascaris lumbricoides), Asian schistosoma (Schistosoma japonicum), and tapeworm (Taenia sp.). We also examine possible factors that favored the spread of these endoparasites among early humans. Therefore, this paper not only aims to reveal how humans have been affected by endoparasites, but also addresses how early medical knowledge developed to cope with the parasitic diseases.

Capillaria Ova and Diagnosis of Trichuris trichiura Infection in Humans by Kato-Katz Smear, Liberia.

We examined human stool samples from Liberia for soil-transmitted helminth ova by Kato-Katz smear and by quantitative PCR. Twenty-five samples were positive for Trichuris trichiura by smear but negative by quantitative PCR. Reexamination of samples showed that they contained Capillaria eggs that resemble T. trichiura in Kato-Katz smears.

[Report on 16 cases of small intestine ascariasis diagnosed by capsule endoscopy].

The clinical data and capsule endoscopy image of 16 adult patients with small intestine ascariasis were reviewed and analyzed retrospectively from June 2006 to June 2012 in West China Hospital. Among the 16 patients, 15 cases manifested as gastrointestinal bleeding, 15 cases showed anemia (3 severe, 10 moderate, and 2 mild), 2 had hypoalbuminemia, 1 had peripheral blood eosinophilia. All the cases were found to be fecal occult blood positive, but no Ascaris eggs found in the feces. Capsule endoscopy showed they were infected with Ascaris worms. The worms were found in the proximal small intestine in 14 patients and 2 in the distal intestine. Mucosal erythema and erosions around the worm were observed in 3 cases, and 7 cases were found with active bleeding or old haemorrhage in small intestine.

[Elimination of juvenile stages of Ascaris lumbricoides (Linnaeus, 1758) by mouth. Report of a case and some epidemiological considerations]. / Eliminación de estadios juveniles de Ascaris lumbricoides (Linneo, 1758) por via oral. Reporte de un caso y algunas consideraciones epidemiológicas.

Ascariosis is a parasitic disease caused by Ascaris lumbricoides, a large geohelmint endemic in our country. At present, ascariosis is a rare infection in Chile. We present a case of an adult, resident of the Villa Alemana municipality, Valparaiso Region, who spontaneously expelled two juvenile nematodes by mouth. We review the manifestations produced by the larval and adult stages of this parasite including their diagnosis, treatment, and epidemiological considerations.

Eliminación de estadios juveniles de Ascaris lumbricoides (Linneo, 1758) por via oral: Reporte de un caso y algunas consideraciones epidemiológicas / Elimination of juvenile stages of Ascaris lumbricoides (Linnaeus, 1758) by mouth: Report of a case and some epidemiological considerations

Ascariosis is a parasitic disease caused by Ascaris lumbricoides, a large geohelmint endemic in our country. At present, ascariosis is a rare infection in Chile. We present a case of an adult, resident of the Villa Alemana municipality, Valparaiso Region, who spontaneously expelled two juvenile nematodes by mouth. We review the manifestations produced by the larval and adult stages of this parasite including their diagnosis, treatment, and epidemiological considerations.

La ascariosis es una parasitosis provocada por Ascaris lumbricoides, el geo-helminto de mayor tamaño que afecta al ser humano en nuestro país. En Chile, la ascariosis es una infección poco frecuente en la actualidad. Se presenta el caso de un adulto residente en la comuna de Villa Alemana, Región de Valparaíso, que eliminó en forma espontánea dos ejemplares del nemátodo en estado juvenil por vía oral. Se revisan las manifestaciones producidas por este parásito en la fase larvaria y adulta, el diagnóstico, el tratamiento y algunas consideraciones epidemiológicas.

Peritonitis secundaria a una perforación por infestación con «Ascaris lumbricoides» / Intestinal perforation with secondary peritonitis caused by Ascaris lumbricoides

La perforación intestinal y la peritonitis secundaria causada por Ascaris lumbricoides, aunque es rara en nuestro medio, debe tenerse en cuenta en los pacientes con clínica compatible procedentes de áreas endémicas. Presentamos el caso de una niña rumana con un cuadro clínico de fiebre, vómitos y dolor abdominal de 15 días de evolución, con colecciones abdominales observadas en las pruebas de imagen, en las que se aprecia una infestación por A. lumbricoides tras la cirugía laparoscópica (AU)

Intestinal perforation with secondary peritonitis caused by Ascaris lumbricoides is rare in our environment. This entity should be taken into consideration in patients who come from endemic areas, and who have suggestive clinical manifestations. We report a case of a Rumanian girl with 15 days of fever, stomach pains and vomiting. Imaging studies evidenced abdominal collections in which Ascaris lumbricoides infestation was found through laparoscopic surgery (AU)

Comparison of the structures of natural and re-established populations of Ascaris in humans in a rural community of Jiangxi, China.

To compare the structures of natural and re-established populations of Ascaris in humans, universal (mass) chemotherapy was carried out at the beginning and the end of the study year using pyrantel pamoate. Worms expelled within 48 h of treatment were collected, their sex determined, and measurements made of length, width and weight. Length was used as the criterion for estimating the developmental stage of the worms. In comparison with the natural population, the reestablished population displayed similar sex ratio as well as distribution patterns among individuals and age groups of the host. However, the mean worm burden of the re-established population was significantly decreased, with a reduction of burdens in children aged 5-9 years. Also, the re-established population showed significant changes in population structure and worm measurements in that it comprised more immature and less fertile males, less fertile and more senile females, smaller and lighter males, larger (but not heavier) females than the natural population. The results suggested that the reestablished Ascaris population did not restore to its original status in relation to mean density, composition and fecundity. Therefore, universal treatment once a year should decrease the transmission of Ascaris in humans. Combined with previous results for the same study sites, the present findings also indicated that caution is warranted to avoid misleading conclusions when using prevalence and faecal egg counts as parameters for evaluating the success of control programmes.

La insólita ingestión de una sonda nasogástrica por un Ascaris lumbricoides / The unusual ingestion of a nasogastric tube by ascaris lumbricoides

Describimos el caso de la insólita ingestión de una sonda de Levin por un Ascaris lumbricoides que se encontraba en el estómago de una pacientes de 60 años de edad, y que había fallecido con el diagnóstico clínico de enfermedad vascular cerebral. Material y método. El parásito fue estudiado en cortes histológicos seriados con el método de hematoxilina-eosina para demostrar la sonda in situ. Resultados. Los cortes mostraron pérdida de la luz trirradial del tracto difestivo y distensión del borde interno y las estructuras como el útero, que permitieron la identificación del parásito y los efectos compresivos de la sonda de Levin. Conclusiones. Considerando que el esófago del parásito es muscular, éste se dilata al extremo de tolerar una sonda que permitió su llegada hasta el recto. Este hallazgo, aunado a la presencia de enzimas líticas en la boca del verme, contribuye a la diversa patología observada en la literatura

The electrical and mechanical activity of the esophageal cell of Ascaris lumbricoides.

The esophagus of Ascaris is a syncytial muscle organ of tubular shape in which the myofibrils are arranged radially between the lumen and the external surface. A resting potential of almost 40 mv (cytoplasm negative) is maintained by the extracellular organic anions (volatile fatty acids) found in the perienteric fluid. Replacement of these anions by Cl- ions results in a large depolarization. The resting potential is also decreased when the external pH is lowered. The leading phase of the action potential with a positive overshoot of about 18 mv elicits contraction of the myofibrils, development of negative pressure within the lumen, and suction of liquid and food particles. The mechanical energy stored in the elastic components of the cell is released when the myofibrils relax, thus injecting the contents of the lumen into the intestine. A fast and synchronous relaxation is elicited by a regenerative membrane polarization, a negative spike with a peak value of up to 108 mv produced by an increase in the permeability of the membrane to K+ ions. Cells completely depolarized in "chloride" saline are still able to generate such large potassium spikes.