Impacto de una intervención de «no hacer» en 12 determinaciones de laboratorio / Impact of a do-not-do intervention on 12 laboratory measurements

Objetivos. En los últimos años distintas sociedades científicas y organizaciones sanitarias han generado recomendaciones orientadas a disminuir las intervenciones sanitarias que no han demostrado eficacia o efectividad. El objetivo de este estudio es evaluar el impacto de una intervención acerca de 12 recomendaciones de «no hacer» referidas al laboratorio en 7 centros hospitalarios. Métodos. Estudio antes-después llevado a cabo en 7 centros hospitalarios de Córdoba y Jaén durante los años 2015 y 2016. Se consensuaron según las recomendaciones de las sociedades científicas existentes diferentes actuaciones referidas a determinaciones de laboratorio. Se analizaron el número y coste de las determinaciones de 6 marcadores tumorales [(antígeno carcinoembrionario, antígeno prostático específico, antígeno carbohidrato (CA) 15.3, CA125, CA19.9 y alfa-fetoproteína)], tirotropina, T3, T4, hemoglobina glicada, urea, ferritina y anticuerpos antigliadina, antes y después de la implantación del consenso. Resultados. Se dejaron de hacer en el año 2016 respecto al año anterior 55.902 determinaciones de laboratorio (-19%), con un ahorro global de 82.100€. La reducción en el número de determinaciones se produjo principalmente en la urea plasmática (-50,3%) y en los marcadores tumorales CA125 (-16%), CA19.9 (-11,6%) y CA15.3 (-10,5%). El ahorro más acusado se obtuvo en la determinación de urea (-21.002€), en la de hormonas tiroideas (-12.716€) y tirotropina (-7.638€). Conclusiones. La adopción y consenso de recomendaciones de «no hacer» entre niveles asistenciales conlleva una reducción significativa de las determinaciones innecesarias (AU)

Objectives. In recent years, various scientific societies and healthcare organisations have created recommendations aimed at decreasing the use of healthcare interventions that have shown no efficacy or effectiveness. The aim of this study was to assess the impact of an intervention on 12 do-not-do recommendations regarding the laboratory in 7 hospital centres. Methods. Before-after study conducted in 7 hospital centres of Cordoba and Jaen during 2015 and 2016. Based on the recommendations of existing scientific societies, a consensus was reached on various actions regarding laboratory measurements. We analysed the number and cost of measuring 6 tumour markers (carcinoembryonic antigen, prostate-specific antigen, carbohydrate antigen [CA] 15.3, CA125, CA19.9 and alpha-fetoprotein), thyrotropin, T3, T4, glycated haemoglobin, urea, ferritin and antigliadin antibodies, before and after implementing the consensus. Results. Compared with the previous year, there were 55,902 fewer laboratory measurements (-19%) in 2016, with an overall savings of €82,100. The reduction in the number of measurements occurred mainly in plasma urea (-50.3%) and in the tumour markers CA125 (-16%), CA19.9 (-11.6%) and CA15.3 (-10.5%). The most pronounced savings were achieved in the measurements of urea (-€21,002), thyroid hormones (-€12,716) and thyrotropin (-€7,638). Conclusions. The adoption and consensus of do-not-do recommendations among healthcare levels resulted in a significant reduction in unnecessary measurements (AU)

Impact of a do-not-do intervention on 12 laboratory measurements. / Impacto de una intervención de «no hacer¼ en 12 determinaciones de laboratorio.

OBJECTIVES: In recent years, various scientific societies and healthcare organisations have created recommendations aimed at decreasing the use of healthcare interventions that have shown no efficacy or effectiveness. The aim of this study was to assess the impact of an intervention on 12 do-not-do recommendations regarding the laboratory in 7 hospital centres. METHODS: Before-after study conducted in 7 hospital centres of Cordoba and Jaen during 2015 and 2016. Based on the recommendations of existing scientific societies, a consensus was reached on various actions regarding laboratory measurements. We analysed the number and cost of measuring 6 tumour markers (carcinoembryonic antigen, prostate-specific antigen, carbohydrate antigen [CA] 15.3, CA125, CA19.9 and alpha-fetoprotein), thyrotropin, T3, T4, glycated haemoglobin, urea, ferritin and antigliadin antibodies, before and after implementing the consensus. RESULTS: Compared with the previous year, there were 55,902 fewer laboratory measurements (-19%) in 2016, with an overall savings of €82,100. The reduction in the number of measurements occurred mainly in plasma urea (-50.3%) and in the tumour markers CA125 (-16%), CA19.9 (-11.6%) and CA15.3 (-10.5%). The most pronounced savings were achieved in the measurements of urea (-€21,002), thyroid hormones (-€12,716) and thyrotropin (-€7,638). CONCLUSIONS: The adoption and consensus of do-not-do recommendations among healthcare levels resulted in a significant reduction in unnecessary measurements.

Can we shorten the lactose tolerance test?

BACKGROUND: Lactose malabsorption (LM) is a very common problem with high prevalence in Southern Europe. The lactose tolerance test (LTT) is a basic probe, which is widespread in local hospitals, because it requires non-complex and inexpensive infrastructure. The aims of our study are to determine that a reduction in the duration of LTT does not affect its diagnostic accuracy to detect LM and to calculate the savings that this reduction may represent. METHODS: A prospective study of consecutive patients who underwent LTT for suspected LM was conducted. We analyzed and compared the clinical results and costs (extraction, analytical measurement, time spent by nursing staff, technicians and patients) of suppressing LTT points at 30 and 120 min. RESULTS: The study included 201 patients. Pathological LTT was found in 119 cases. Eliminating the measurement of glucose at 120 min did not alter the LTT interpretation in any patient; however, up to 18.4% of patients had a LTT misinterpretation when the 30 min point was suppressed. If the LTT 120 min measurement would have been suppressed, 41,334 euros could have been saved. CONCLUSIONS: Suppressing the 120 min LTT point does not imply any changes in clinical results and reduces patient's waiting time; it also benefits the health system by saving time, manpower and materials.

Evaluation of third generation anti-CCP antibodies in the diagnosis of rheumatoid arthritis from undifferentiated polyarthritis after 4 years of follow-up.

OBJECTIVES: Rheumatoid arthritis (RA) is a complex pathology to identify at an early stage. A large number of patients with recent onset polyarthritis (ROP) do not usually fulfil the ACR criteria for diagnosis of the disease and are classified as having undifferentiated polyarthritis. The aim of this study is to verify with certainty the diagnosis of patients whose illness has not been classified after four years of follow-up, and correlate their actual status with the levels of anti-cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor (RF) found. METHODS: After one year of follow-up, 56 patients from a total of 322, included from January 2002 in the ROP Unit, did not meet ACR criteria for any rheumatic disease. The anti-CCP antibodies and RF levels were determined in the initial clinical assessment. RESULTS: After four years of follow-up, 12 new diagnoses were made in the 56 patients with undifferentiated polyarthritis: 3 seronegative RA, 8 seropositive RA and 1 psoriatic arthritis. The anti-CCP antibodies levels were positive for 5 of these 12 patients (median anti-CCP 228.6 U/mL), and all were RF positive. Six of the 7 anti-CCP antibodies negative patients were diagnosed of RA (3 seropositive and 3 seronegative for RF) and 1 was diagnosed of psoriatic arthritis (anti-CCP antibodies negative and RF positive). Forty-four patients still displayed undifferentiated polyarthritis and were RF negative. CONCLUSION: A positive result for RF and anti-CCP antibodies in patients who do not meet the ACR diagnostic criteria could be a useful indicator of the presence of future RA.

A recent onset inflammatory polyarthritis register in Spain: factors that predict remission.

OBJECTIVE: To identify baseline variables that predict remission at 1 year in patients with recent onset inflammatory polyarthritis (IP). METHODS: We prospectively studied 167 patients aged >or=16 years with a 4-week to 12-month history of swelling of >or=2 joints. At baseline, no patient had previously received corticosteroids or disease-modifying anti-rheumatic drugs (DMARDs). To adjust for differences in baseline variables associated with the type of treatment given (a surrogate marker of disease severity), we used regression analysis. The classification probability of treatment thus obtained was entered, along with other significant baseline variables, in a second separate regression analysis to identify variables that predicted remission (no swollen joints). RESULTS: Frequency of remission was 50.9% at 1 year. In the first regression analysis, variables associated with treatment with DMARDs or DMARDs and corticosteroids versus corticosteroids alone included age, morning stiffness, swollen joint count (SJC), disease severity according to the patient, and rheumatoid factor (RF) level; the strongest association was for higher SJC. In the second regression analysis, the model that best predicted remission (correct in 70.1% of cases) included age, tender joint count (TJC), erythrocyte sedimentation rate (ESR), RF, total Sharp score, disease severity according to the physician, and the 1987 American Rheumatism Association (ARA) criteria for rheumatoid arthritis (RA); the strongest association was for failure to meet these criteria. The model's sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve were 70.6%, 70.9%, and 75.4%, respectively. CONCLUSION: Although we identified some predictors of remission, no model accurately predicted remission at 1 year in this cohort.

[Influence of the delay in urinary NMP22 preanalytical processing]. / Influencia del retraso en el procesamiento preanalítico de la orina en la determinacin del NMP22.

OBJECTIVES: To evaluate the influence of the delay in urinary NMP22 preanalytical processing. MATERIAL AND METHODS: Twenty-eight voided urine samples were taken: bladder cancer (14), urine tract infections (4), lithiasis (4), healthy volunteers (1), and with other no malignant bladder diseases (5). All samples, were maintained at environment temperature, and were processed according to the stabilization of parts of urine collected at 0, 30, 90 and 150 minutes. Samples were stored at 4 degrees C until its determination. NMP22 was determined with the IMMULITE One analyzer. RESULTS: There were no significant differences for NMP22 levels between each different point of time studied. CONCLUSIONS: Delay up to 2 hours and a half when we add stabilization solution to urine samples no affects NMP22 results. That thing, might provide more confidence and flexibility on quantitative immunoassays that required urine stabilization.

Influencia del retraso en el procesamiento preanalítico de la orina en la determinación del NMP22 / Influence of the delay in urinary NMP22 preanalytical processing

Objetivo: Evaluar la influencia del retraso en el procesamiento preanalítico de orinas en las que se realiza la determinación del marcador tumoral NMP22. Material y métodos: Se recogieron 28 muestras de orina: tumores vesicales (14), infecciones urinarias (4), litiasis (4), voluntarios sanos (1), y otras patologías vesicales benignas (5). De cada muestra, mantenida a temperatura ambiente, se fueron estabilizando alícuotas con el conservante suministrado por el fabricante a los 0, 30, 90 y 150 minutos, guardándose a 4ºC hasta su procesamiento. El análisis del NMP22 se realizó en autoanalizador IMMULITE One. Resultados: No se apreciaron diferencias significativas en los niveles del NMP22 entre los diferentes puntos de demora estudiados. Conclusiones: La demora de hasta dos horas y media en la adición de la solución conservante a la orina para determinación de NMP22 no afecta significativamente a los resultados obtenidos. Este hecho permite una mayor confianza y flexibilidad en los inmunoensayos cuantitativos que requieren estabilización de la muestra

Objectives: To evaluate the influence of the delay in urinary NMP22 preanalytical processing. Material and methods: Twenty-eight voided urine samples were taken: bladder cancer (14), urine tract infections (4), lithiasis (4), healthy volunteers (1), and with other no malignant bladder diseases (5). All samples, were maintained at environment temperature, and were processed according to the stabilization of parts of urine collected at 0, 30, 90 and 150 minutes. Samples were stored at 4 ºC until its determination. NMP22 was determined with the IMMULITE One analyzer. Results: There were no significant differences for NMP22 levels between each different point of time studied. Conclusions: Delay up to 2 hours and a half when we add stabilization solution to urine samples no affects NMP22 results. That thing, might provide more confidence and flexibility on quantitative immunoassays that required urine stabilization

Clinical and ethical implications of genetic counselling in familial adenomatous polyposis.

The association of specific genetic disturbances with the development of hereditary cancer helps us to understand the risk of suffering from it, the possibility of an earlier diagnosis, and the treatment and prevention of this disease. Familial adenomatous polyposis (FAP) is a pre-neoplastic syndrome characterized by the presence of hundreds of adenomatous polyps in the colon, which develop into a carcinoma. FAP can be diagnosed using sequencing techniques to detect mutations in the germinal line of the APC (adenomatous polyposis coli) gene. The genetic diagnostic approach in families with FAP, previously followed up in the Gastrointestinal Clinic, has both advantages and disadvantages, and places us nearer the disease and patient. Disclosing the results of this genetic test entails relevant problems in clinical practice, which affect the health field and raise legal and ethical issues, along with the familial, occupational, and social implications that knowing the genetic status can have on the patient. Genetic analysis is rare in normal clinical practice, which involves errors in the interpretation of the results obtained, and during the process of genetic counselling. Specialized multidisciplinary units are necessary for the management of patients with FAP undergoing analysis and appropriate genetic counselling, thus providing an individualized service. The creation of FAP registers and protocols for this healthcare process should optimize the management of these patients and their families.

Implicaciones clínicas y éticas del consejo genético en la poliposis adenomatosa familiar / Clinical and ethical implications of genetic counselling in familial adenomatous polyposis

La asociación de determinadas alteraciones genéticas con laaparición de cáncer hereditario, nos permite conocer el riesgo depadecerlo, posibilitando el diagnóstico precoz, el tratamiento y laprevención de la enfermedad. La poliposis adenomatosa familiar(PAF) es un síndrome preneoplásico que se caracteriza por la presenciade cientos de pólipos adenomatosos en colon, que evolucionaránhacia carcinoma. La PAF puede ser diagnosticada mediantetécnicas de secuenciación que detectan mutaciones en lalínea germinal del gen APC (adenomatous poliposis coli).El abordaje del diagnóstico genético en familias con PAF seguidaspreviamente en la consulta de digestivo, ha permitido ponerde manifiesto tanto las ventajas como los inconvenientes de estaforma de acercarnos a la enfermedad y a los pacientes. La revelaciónde los resultados de la prueba genética comporta importantesproblemas en la práctica clínica, que afectan tanto al ámbito sanitario,como al ético y legal, además de las implicaciones familiares,laborales y sociales que el conocimiento del status genéticopuede tener para el paciente.El análisis genético es poco frecuente en la práctica clínica habitual,lo que conlleva errores tanto en la interpretación de los resultadosobtenidos como durante el proceso del consejo genético.Son necesarias unidades multidisciplinares especializadas en elmanejo de pacientes con PAF, en las cuales se realice un análisis yun consejo genético adecuado, permitiendo así una atención personalizada.La creación de registros de PAF y la protocolizaciónde este proceso sanitario debería optimizar el manejo de estos pacientesy sus familias

The association of specific genetic disturbances with the developmentof hereditary cancer helps us to understand the risk of sufferingfrom it, the possibility of an earlier diagnosis, and the treatmentand prevention of this disease. Familial adenomatouspolyposis (FAP) is a pre-neoplastic syndrome characterized by thepresence of hundreds of adenomatous polyps in the colon, whichdevelop into a carcinoma. FAP can be diagnosed using sequencingtechniques to detect mutations in the germinal line of the APC(adenomatous polyposis coli) gene.The genetic diagnostic approach in families with FAP, previouslyfollowed up in the Gastrointestinal Clinic, has both advantagesand disadvantages, and places us nearer the disease and patient.Disclosing the results of this genetic test entails relevantproblems in clinical practice, which affect the health field and raiselegal and ethical issues, along with the familial, occupational, andsocial implications that knowing the genetic status can have onthe patient.Genetic analysis is rare in normal clinical practice, which involveserrors in the interpretation of the results obtained, and duringthe process of genetic counselling. Specialized multidisciplinaryunits are necessary for the management of patients with FAPundergoing analysis and appropriate genetic counselling, thusproviding an individualized service. The creation of FAP registersand protocols for this healthcare process should optimize themanagement of these patients and their families

Intoxicaciones agudas en un medio rural asturiano / Acute intoxications in asturiano rural mielieu

No disponible

Immature granulocyte detection by the SE-9000 haematology analyser during pregnancy.

The objective of this study was to determine the nature of the alarm for immature granulocytes appearing in haemograms from pregnant women, as detected by the immature cell information channel (IMI) of the SE-9000 automated haematology analyser. Of all tests run on pregnant women in a 4-month period (n = 698), the first 100 haemograms with immature granulocyte alarms (14.33%) were collected. Each of these samples was then stained with Wright-Giemsa stain. The following variables were also analysed: age of the mother, trimester and days of gestation, type of delivery, weight and sex of the baby, and Apgar score. Most pregnant women were in the third trimester of gestation (82%) when an alarm was noted on the IMI channel. Of the patients, 62% had normal deliveries. The most frequent complication was obstructed delivery (23%). Mean percentages by microscopic counts of band cells, metamyelocytes, and myelocytes were 2.99, 0.45, and 0.19%, respectively. There was a statistically significant correlation for all cell types between the SE-9000 and the manual count method. No association was observed between the presence of immature granulocytes and the clinical variables analysed. The SE-9000 analyser shows high sensitivity in the IMI channel for detection of immature forms.

[Attitudes of health centre users to diagnoses of terminal illness]. / Actitud de los usuarios de centro de salud ante el diagnóstico de enfermedad terminal.

OBJECTIVE: To calculate the prevalence of users who want to know their diagnosis of terminal illness and to analyse the factors determining their decision. DESIGN: Descriptive, observational, cross-sectional study. SETTING: Six lists belonging to two Health Districts in Asturias Health Area III. PARTICIPANTS: On-demand users of the clinic, over 17 years old, selected by systematic randomized sampling stratified according to the number of consultations at the centre. MAIN MEASUREMENTS AND RESULTS: Through a questionnaire composed by the researchers and face-to-face interviews, social and personal variables and attitudes to a diagnosis of terminal illness were collected. The sample consisted of 388 people. A descriptive analysis and population calculations were made, with a logistical regression analysis to identify associated variables. RESULTS: 70.6% of those questioned (95% CI, 66%-75.1%) wanted to know their diagnosis, mainly on the basis of their right to the information (35.1%; 95% CI, 29%-40.6%). Most of these wanted to be informed by the doctor (81.9%; CI, 77.5%-86.5%). The variables significantly linked to a positive reply were: male (OR, 1.91; CI, 1.1%-3.4%), age (OR, 0.97; CI, 0.95%-0.99%), religious beliefs (OR, 0.2; CI, 0.1%-0.8% for believers), fear of pain and disability (OR, 3.8; CI, 1.2%-12%), and having previously thought about wanting to be informed (OR, 2.2; CI, 1.2%-4%). This last variable achieved the highest partial correlation coefficient (R, 0.12). CONCLUSIONS: Most users want to be informed of a diagnosis of terminal illness. The profile of the patient who wants to know the truth is: young male, non-believer, and someone whose main fears of terminal illness are pain and disability. The variable with most influence on the positive reply was having posed the question previously.

Actitud de los usuarios de centro de salud ante el diagnóstico de enfermedad terminal / Attitudes of health centre users to diagnoses of terminal illness

Objetivo. Estimar la prevalencia de usuarios que desearían conocer el diagnóstico de enfermedad terminal y analizar los condicionantes relacionados con dicha decisión. Diseño. Estudio descriptivo, observacional, transversal. Emplazamiento. Seis cupos pertenecientes a dos zonas básicas de salud del Área Sanitaria III de Asturias. Participantes. Usuarios de consulta a demanda, mayores de 17 años, seleccionados por muestreo aleatorio sistemático estratificado según el número de consultas del centro. Se excluyó a sujetos diagnosticados de enfermedad terminal y/o con problemas de comunicación. Mediciones y resultados principales. Mediante encuesta de elaboración propia y entrevista personal, se recogieron variables sociodemográficas y de actitud frente al diagnóstico de enfermedad terminal. El tamaño de la muestra fue de 388 individuos. Se realizó análisis descriptivo y estimaciones poblacionales, aplicándose análisis de regresión logística para identificar variables asociadas. Resultados. El 70,6 per cent de los encuestados (intervalo de confianza [IC] del 95 per cent, 66-75,1 per cent) desearía conocer el diagnóstico, alegando principalmente el derecho a la información (el 35,1 per cent; IC del 95 per cent, 29-40,6 per cent). Mayoritariamente querrían ser informados por el médico (el 81,9 per cent; IC del 95 per cent, 77,586,5 per cent). Las variables que de forma significativa se asociaron con respuesta positiva fueron: varón (odd ratio [OR], 1,91; IC del 95 per cent, 1,1-3,4 per cent), edad (OR, 0,97; IC del 95 per cent, 0,95-0,99 per cent), creencias religiosas (OR: 0,2; IC del 95: 0,1-0,8 per cent para creyentes), temor a dolor e invalidez (OR, 3,8; IC del 95 per cent, 1,2-12 per cent) y planteamiento previo de querer ser informado (OR, 2,2; IC del 95 per cent, 1,2-4 per cent), obteniéndose en el caso de esta última variable el coeficiente de correlación parcial más elevado (R = 0,12). Conclusiones. La mayoría de los usuarios desea ser informada del diagnóstico de enfermedad terminal. El perfil del paciente que desea conocer la verdad responde a: varón joven, no creyente, sus principales temores ante la enfermedad terminal son el dolor y la invalidez, siendo la variable que más influencia ha tenido sobre la respuesta positiva el planteamiento previo de la pregunta. (AU)

Expression of argyrophilic nucleolar organizer regions (AgNORs) in the harderian gland of male and female hamsters during postnatal development.

The expression of argyrophilic nucleolar organizer regions (AgNORs) was studied in the different secretory cell types of the Harderian gland of male and female Syrian hamsters during postnatal development. Mean AgNOR area was calculated for each cell type in paraffin sections from 7-, 14-, 21-, 28-, 45- and 90-day-old animals. AgNOR content was similar in male type I-cells and in female cells, decreasing in both cell types from the 7th to the 14th day, increasing afterwards at the 21st day, and remaining at relatively stable levels from that point to the end of the study. AgNOR content of male type II-cells was greater than in other cell type studied, and was greater in 45- and 90-day-old animals than in 28-day-olds. Changes of AgNOR content in type I-cells of male and female hamsters during the first two weeks seem to be related to changes in proliferative activity while metabolic activity might be responsible for changes taking place later on. Our results also support that male type I- and type II-cells have a different biological behaviour and that type II-cells are far from being degenerating cells.

Matrix solid-phase dispersion technique for the determination of moxidectin in bovine tissues.

An HPLC method has been developed for the determination of moxidectin in bovine tissues. The extraction and clean-up procedure is based on the matrix solid-phase dispersion technique. Control and moxidectin-fortified bovine tissue samples (0.25 g) are blended with octadecyl (C18 end-capped) packing material. A column made from the C18-bovine tissue blend is washed with hexane (2 ml); when all the hexane has eluted, an Alumina-B SPE cartridge is attached below the C18-tissue column and, after washing, moxidectin is eluted with methanol (6 ml). Moxidectin is derivatized and determined by HPLC with fluorescence detection. The recovery from fortified samples was greater than 80% in the concentration range 1-100 ng g-1 of tissue. This method permits the determination of moxidectin at levels as low as 1 ng g-1 (1 ppb).

Postnatal development of cell types in the hamster Harderian gland.

The morphology, frequency, and distribution of mitotic cells in the epithelium of the Harderian gland was studied in the male and female hamster from birth to the ninetieth day of postnatal life using light and electron microscopic techniques. The results obtained show that there is a gradual decline in the mitotic activity of the Harderian gland as the animals become older which continues until sexual maturity is reached. The study did not find any morphological evidence for the existence of separate precursor cells for the different secretory cell types of the gland. Secretory cells seem to be a homogeneous population in the glands of hamsters younger than 20 days. Cells that could be interpreted as undifferentiated stem cells were not observed. Mitotic cells were observed randomly distributed within tubulo-alveoli, similar to those in interphase. The first sex differences were observed at day 20, when type II cells appeared in male glands. From this point, the percentage of type II cells rapidly increased in male glands. This increase was not accompanied by an increase in the global mitotic activity. However, at this age, male type II cells develop an intense mitotic activity. The observations obtained are in accordance with the hypothesis that the type I and type II cells have the same cell precursor.

New insights into the cytodynamics of the hamster Harderian gland as provided by the bromodeoxyuridine-labelling method.

The fourth week of postnatal life is a critical point in the development of the hamster Harderian gland. During this week, cells with large lipid vacuoles (type-II cells) appear in the male gland, marking a morphological sex difference that is notorious in adult animals. The origin and fate of type-II cells are controversial. To gain insight into the mechanisms by which type-II cells become a major cell type in the gland of adult male hamsters, bromodeoxyuridine (BrdU) labelling was used to assess the proliferative activity of both types of glandular cells in 28-day-old animals. To search for possible sex differences in the proliferative activity of this gland, female animals of the same age as the males were also studied. No difference was found in the overall labelling index (BrdU-labelled cells/100 cells) between males (1.8 +/- 0.1%) and females (1.5 +/- 0.1%). In the gland of the males, the specific labelling index of type-II cells (3.4 +/- 0.4%) was significantly higher than that of type-I cells (0.9 +/- 0.2%). Interestingly, the proportion of type-II cells present in the male glands at this age (36.6%) was significantly lower than that of type-I cells. Our results strongly suggest that the proliferation of type-II cells, rather than a continuous differentiation of these cells from preexisting type-I cells, is a major event in the achievement of the mature form of this gland. The results reported here counsel a reappraisal of current theories about the cytodynamics of the hamster Harderian gland.