Detection of unsuspected cathinone and piperazine-type drugs in urine samples positive for methamphetamine and amphetamine collected in emergency departments. / Detección no sospechada de catinonas y piperacinas en pacientes consumidores de metanfetamina y anfetamina atendidos en servicios de urgencias hospitalarios.

OBJECTIVES: To detect the presence of unsuspected and/or undeclared cathinone and piperazine-type designer drugs in methamphetamine (METH) and amphetamine users treated in emergency departments, and to compare clinical and toxicologic profiles. MATERIAL AND METHODS: Retrospective observational study of emergency department patients treated for confirmed acute intoxication by recreational drugs (METH and amphetamines) between March 2019 and December 2020. We ordered high-performance liquid chromatography with tandem mass spectrometry to detect cathinones (methylone, fluoromethcathinone, mexedrone, fluoromethamphetamine, mephedrone, methylenedioxypyrovalerone) and synthetic piperazines (meta-chlorophenylpiperazine and trifluoromethylphenylpiperazine). Demographic, clinical, and toxicologic variables were analyzed with SPSS software (version 23). RESULTS: Thirty-nine patients were included: 24 (61.5%) had used METH and 15 (38.5%) an amphetamine. Synthetic cathinones were detected in samples from 11 patients (28.2%), 10 (90.9%) in the METH group and 1 (9.1%) in the amphetamine group (P = .028). The METH users had taken mephedrone (8 patients) or methylone (2 patients); the amphetamine user had taken mephedrone. None of the patients had declared use of a cathinone; nor was use suspected. The mean (SD) number of substances involved was higher among users of cathinones (3.5 [1.13] vs 2.5 [1.40] in those who took no cathinones; P = .036). Among the cathinone users, 90.9% were men, 90.9% had used METH, and 45.5% had practiced chemsex. HIV positivity was significantly associated with cathinone use (in 45.5% vs 10.7% of those not using cathinones; P = .028). All 5 of the patients who had taken cathinones and also practiced chemsex were HIV positive. Significantly more patients who had taken cathinones presented with anxiety (72.7% vs 21.43%; P = .007). No differences in clinical management were found. CONCLUSION: Detection of METH in intoxicated patients should raise suspicion of probable use of a synthetic cathinone. Patients in whom new psychoactive substances are detected should be kept under observation, and clinical protocols should include referring them to addiction treatment centers.

OBJETIVO: Determinar la incidencia de catinonas y piperazinas, no sospechadas y/o declaradas en consumidores de metanfetamina (MANF) y anfetamina (ANF) atendidos en servicios de urgencias hospitalarios (SUH) y comparar los perfiles clínicos y toxicológicos. METODO: Estudio retrospectivo de pacientes con intoxicación aguda por drogas recreativas con MANF y ANF confirmadas analíticamente atendidos en 3 SUH entre marzo de 2019 y diciembre de 2020. Se detectaron por HPLC-MS/MS las catinonas [metilona, fluorometcatinona, mecedrona, fluorometanfetamina, mefedrona, metilendioxipirovalerona (MDPV)] y las piperazinas sintéticas [meta-clorofenilpiperazina (mCPP), trifluorometilfenilpiperazina (TFMPP)]. RESULTADOS: Se incluyeron 39 pacientes: 24 (61,5%) en el grupo MANF y 15 (38,5%) en el ANF. En 11 (28,2%), se detectaron catinonas sintéticas (grupo CAT), 10 en el grupo MANF (8 mefedrona, 2 metilona) y 1 en el grupo ANF (1 mefedrona) (90,9% vs 9,1%; p = 0,028). Ninguno de los pacientes declaró consumo de catinonas. El número de drogas implicadas en la intoxicación fue superior en el grupo CAT (3,5 [1,13] vs 2,5 [1,40]; p = 0,036). El perfil clínico del grupo CAT fue: varón (90,9%), consumidor de MANF (90,9%) y usuario de chemsex (45,5%). El diagnóstico de VIH se asoció significativamente al grupo CAT (45,5% vs 10,7%; p = 0,028). Los pacientes del grupo CAT presentaron mayor ansiedad (72,7% vs 21,4%; p = 0,007). No se hallaron diferencias en su manejo clínico. CONCLUSIONES: La detección de MANF debería considerarse un dato de sospecha de consumo de catinonas sintéticas, y en esos casos debería contemplarse la detección de nuevas sustancias psicoactivas de abuso.

Detección no sospechada de catinonas y piperacinas en pacientes consumidores de metanfetamina y anfetamina atendidos en servicios de urgencias hospitalarios / Detection of unsuspected cathinone and piperazine-type drugs in urine samples positive for methamphetamine and amphetamine collected in emergency departments

Objetivos. Determinar la incidencia de catinonas y piperazinas, no sospechadas y/o declaradas en consumidores de metanfetamina (MANF) y anfetamina (ANF) atendidos en servicios de urgencias hospitalarios (SUH) y comparar los perfiles clínicos y toxicológicos. Método. Estudio retrospectivo de pacientes con intoxicación aguda por drogas recreativas con MANF y ANF confirmadas analíticamente atendidos en 3 SUH entre marzo de 2019 y diciembre de 2020. Se detectaron por HPLC-MS/MS las catinonas [metilona, fluorometcatinona, mecedrona, fluorometanfetamina, mefedrona, metilendioxipirovalerona (MDPV)] y las piperazinas sintéticas [meta-clorofenilpiperazina (mCPP), trifluorometilfenilpiperazina (TFMPP)]. Resultados. Se incluyeron 39 pacientes: 24 (61,5%) en el grupo MANF y 15 (38,5%) en el ANF. En 11 (28,2%), se detectaron catinonas sintéticas (grupo CAT), 10 en el grupo MANF (8 mefedrona, 2 metilona) y 1 en el grupo ANF (1 mefedrona) (90,9% vs 9,1%; p = 0,028). Ninguno de los pacientes declaró consumo de catinonas. El nú- mero de drogas implicadas en la intoxicación fue superior en el grupo CAT (3,5 [1,13] vs 2,5 [1,40]; p = 0,036). El perfil clínico del grupo CAT fue: varón (90,9%), consumidor de MANF (90,9%) y usuario de chemsex (45,5%). El diagnóstico de VIH se asoció significativamente al grupo CAT (45,5% vs 10,7%; p = 0,028). Los pacientes del grupo CAT presentaron mayor ansiedad (72,7% vs 21,4%; p = 0,007). No se hallaron diferencias en su manejo clínico. Conclusiones. La detección de MANF debería considerarse un dato de sospecha de consumo de catinonas sintéticas, y en esos casos debería contemplarse la detección de nuevas sustancias psicoactivas de abuso.

Objectives. To detect the presence of unsuspected and/or undeclared cathinone and piperazine-type designer drugs in methamphetamine (METH) and amphetamine users treated in emergency departments, and to compare clinical and toxicologic profiles. Method. Retrospective observational study of emergency department patients treated for confirmed acute intoxication by recreational drugs (METH and amphetamines) between March 2019 and December 2020. We ordered high-performance liquid chromatography with tandem mass spectrometry to detect cathinones (methylone, fluoromethcathinone, mexedrone, fluoromethamphetamine, mephedrone, methylenedioxypyrovalerone) and synthetic piperazines (meta-chlorophenylpiperazine and trifluoromethylphenylpiperazine). Demographic, clinical, and toxicologic variables were analyzed with SPSS software (version 23). Results. Thirty-nine patients were included: 24 (61.5%) had used METH and 15 (38.5%) an amphetamine. Synthetic cathinones were detected in samples from 11 patients (28.2%), 10 (90.9%) in the METH group and 1 (9.1%) in the amphetamine group (P = .028). The METH users had taken mephedrone (8 patients) or methylone (2 patients); the amphetamine user had taken mephedrone. None of the patients had declared use of a cathinone; nor was use suspected. The mean (SD) number of substances involved was higher among users of cathinones (3.5 [1.13] vs 2.5 [1.40] in those who took no cathinones; P = .036). Among the cathinone users, 90.9% were men, 90.9% had used METH, and 45.5% had practiced chemsex. HIV positivity was significantly associated with cathinone use (in 45.5% vs 10.7% of those not using cathinones; P = .028). All 5 of the patients who had taken cathinones and also practiced chemsex were HIV positive. Significantly more patients who had taken cathinones presented with anxiety (72.7% vs 21.43%; P = .007). No differences in clinical management were found. [...]

Harmonized D-dimer levels upon admission for prognosis of COVID-19 severity: Results from a Spanish multicenter registry (BIOCOVID-Spain study).

Coagulopathy is a key feature of COVID-19 and D-dimer has been reported as a predictor of severity. However, because D-dimer test results vary considerably among assays, resolving harmonization issues is fundamental to translate findings into clinical practice. In this retrospective multicenter study (BIOCOVID study), we aimed to analyze the value of harmonized D-dimer levels upon admission for the prediction of in-hospital mortality in COVID-19 patients. All-cause in-hospital mortality was defined as endpoint. For harmonization of D-dimer levels, we designed a model based on the transformation of method-specific regression lines to a reference regression line. The ability of D-dimer for prediction of death was explored by receiver operating characteristic curves analysis and the association with the endpoint by Cox regression analysis. Study population included 2663 patients. In-hospital mortality rate was 14.3%. Harmonized D-dimer upon admission yielded an area under the curve of 0.66, with an optimal cut-off value of 0.945 mg/L FEU. Patients with harmonized D-dimer ≥ 0.945 mg/L FEU had a higher mortality rate (22.4% vs. 9.2%; p < 0.001). D-dimer was an independent predictor of in-hospital mortality, with an adjusted hazard ratio of 1.709. This is the first study in which a harmonization approach was performed to assure comparability of D-dimer levels measured by different assays. Elevated D-dimer levels upon admission were associated with a greater risk of in-hospital mortality among COVID-19 patients, but had limited performance as prognostic test.

Cardiac troponin and COVID-19 severity: Results from BIOCOVID study.

BACKGROUND: Myocardial injury is a common finding in COVID-19 strongly associated with severity. We analysed the prevalence and prognostic utility of myocardial injury, characterized by elevated cardiac troponin, in a large population of COVID-19 patients, and further evaluated separately the role of troponin T and I. METHODS: This is a multicentre, retrospective observational study enrolling patients with laboratory-confirmed COVID-19 who were hospitalized in 32 Spanish hospitals. Elevated troponin levels were defined as values above the sex-specific 99th percentile upper reference limit, as recommended by international guidelines. Thirty-day mortality was defined as endpoint. RESULTS: A total of 1280 COVID-19 patients were included in this study, of whom 187 (14.6%) died during the hospitalization. Using a nonspecific sex cut-off, elevated troponin levels were found in 344 patients (26.9%), increasing to 384 (30.0%) when a sex-specific cut-off was used. This prevalence was significantly higher (42.9% vs 21.9%; P < .001) in patients in whom troponin T was measured in comparison with troponin I. Sex-specific elevated troponin levels were significantly associated with 30-day mortality, with adjusted odds ratios (ORs) of 3.00 for total population, 3.20 for cardiac troponin T and 3.69 for cardiac troponin I. CONCLUSION: In this multicentre study, myocardial injury was a common finding in COVID-19 patients. Its prevalence increased when a sex-specific cut-off and cardiac troponin T were used. Elevated troponin was an independent predictor of 30-day mortality, irrespective of cardiac troponin assay and cut-offs to detect myocardial injury. Hence, the early measurement of cardiac troponin may be useful for risk stratification in COVID-19.

Characteristics and laboratory findings on admission to the emergency department among 2873 hospitalized patients with COVID-19: the impact of adjusted laboratory tests in multicenter studies. A multicenter study in Spain (BIOCOVID-Spain study).

Identification of predictors for severe disease progression is key for risk stratification in COVID-19 patients. We aimed to describe the main characteristics and identify the early predictors for severe outcomes among hospitalized patients with COVID-19 in Spain. This was an observational, retrospective cohort study (BIOCOVID-Spain study) including COVID-19 patients admitted to 32 Spanish hospitals. Demographics, comorbidities and laboratory tests were collected. Outcome was in-hospital mortality. For analysis, laboratory tests values were previously adjusted to assure the comparability of results among participants. Cox regression was performed to identify predictors. Study population included 2873 hospitalized COVID-19 patients. Nine variables were independent predictors for in-hospital mortality, including creatinine (Hazard ratio [HR]:1.327; 95% Confidence Interval [CI]: 1.040-1.695, p = .023), troponin (HR: 2.150; 95% CI: 1.155-4.001; p = .016), platelet count (HR: 0.994; 95% CI: 0.989-0.998; p = .004) and C-reactive protein (HR: 1.037; 95% CI: 1.006-1.068; p = .019). This is the first multicenter study in which an effort was carried out to adjust the results of laboratory tests measured with different methodologies to guarantee their comparability. We reported a comprehensive information about characteristics in a large cohort of hospitalized COVID-19 patients, focusing on the analytical features. Our findings may help to identify patients early at a higher risk for an adverse outcome.

Automated cell count in body fluids: a review.

Body fluid cell counting provides valuable information for the diagnosis and treatment of a variety of conditions. Chamber cell count and cellularity analysis by optical microscopy are considered the gold-standard method for cell counting. However, this method has a long turnaround time and limited reproducibility, and requires highly-trained personnel. In the recent decades, specific modes have been developed for the analysis of body fluids. These modes, which perform automated cell counting, are incorporated into hemocytometers and urine analyzers. These innovations have been rapidly incorporated into routine laboratory practice. At present, a variety of analyzers are available that enable automated cell counting for body fluids. Nevertheless, these analyzers have some limitations and can only be operated by highly-qualified laboratory professionals. In this review, we provide an overview of the most relevant automated cell counters currently available for body fluids, the interpretation of the parameters measured by these analyzers, their main analytical features, and the role of optical microscopy as automated cell counters gain ground.

Intoxicaciones por anfetamina y metanfetamina atendidas en los servicios de urgencias: características clínicas y utilidad de la confirmación analítica / Amphetamine and methamphetamine poisonings attended in hospital emergency departments: clinical features and the usefulness of laboratory confirmation

Objetivo: Investigar si existen diferencias clínicas y toxicológicas en pacientes intoxicados por anfetamina (ANF) y metanfetamina (MANF) atendidos en servicios de urgencias. Método: Estudio observacional retrospectivo de intoxicaciones por ANF y MANF con confirmación analítica en Baleares (2013-2018). Se compararon variables clínicas, toxicológicas y de manejo clínico entre grupos. Resultados: 1) Se incluyeron 120 pacientes, 86 (71,7%) grupo ANF y 34 (28,3%) grupo MANF. 2) La confirmación de derivados anfetamínicos se realizó por cromatografía de gases-espectrometría de masas en 787 muestras de orina previamente positivas mediante un método de cribado cualitativo. Se confirmaron 154 (19,6%) muestras. De ellas, 34 fueron excluidas. 3) Se encontraron diferencias significativas entre ANF y MANF en: edad (32,3 vs 28,4 años); sexo (72,1 vs 94,1% hombres); nacionalidad española (64,0 vs 29,4%); en motivos de admisión: alteración de conducta (15,1 vs 0%) y palpitaciones (1,2 vs 20,6%); y en características clínicas: agitación (27,9 vs 8,8%). No hubo diferencias de manejo clínico. El 76,6% de casos fueron polintoxicaciones, más comunes en ANF (82,6 vs 61,8%). En estos casos se detectó principalmente cocaína (63,0%), cannabis (48,9%), MDMA (38,0%) y alcohol (35,9%). La mayor asociación del cannabis con el grupo de ANF fue estadísticamente significativa (45,3 vs 17,6%). La causa de los falsos positivos se identificó en el 78,7% de muestras, siendo el MDMA (71,2%) la principal. Conclusiones: Se observaron diferencias entre ANF y MANF en cuanto a variables demográficas y motivo de asistencia; no obstante en esta serie hubo un alto porcentaje de polintoxicaciones

Objective: To determine whether clinical and toxicologic findings differed between cases of amphetamine (AMP) and methamphetamine (mAMP) poisoning attended in 2 Balearic Island hospital emergency departments. Methods: Retrospective observational study of AMP and mAMP cases with laboratory confirmation between 2013 and 2018. We compared clinical and toxicologic variables as well as clinical management between groups. Results: 1) A total of 120 cases were found: 86 (71.7%) with AMP poisoning and 34 (28.3%) with mAMP poisoning. 2) Drug poisoning was confirmed by gas chromatography associated with mass spectrometry (GC–MS) in 787 urine samples found to be positive during screening. One hundred fifty-four (19.6%) were confirmed by GC–MS. Thirtyfour of them did not meet the inclusion criteria. 3) Significant differences between AMP and mAMP cases were found for age (32.3 vs 28.4 y, respectively); sex (72.1% vs 94.1% men); and Spanish nationality (64.0% vs 29.4%). Reasons for admission and clinical features also differed: the reasons were aberrant behavior (15.1% in the AMP group vs 0% in the mAMP group) and palpitations (1.2% vs 20.6%); agitation was observed in 27.9% and 8.8%, respectively. Clinical management was similar in the 2 groups. Multiple drug poisoning was detected in 76.6% patients and was more common in patients in the AMP group (82.6% vs 61.8%). The additional drugs in these cases were mainly cocaine (63.0%), cannabis (48.9%), 3,4-methylenedioxy-N-methamphetamine (MDMA) (38.0%), and alcohol (35.9%). Cannabis was detected in a significantly higher proportion in the AMP group (45.3%) than in the mAMP group (17.6%). False positives were found in 78.7% of the samples. The culprit drug was most often MDMA (71.2%). Conclusions: AMP poisonings were associated with age over 30 years, Spanish nationality, aberrant behavior, agitation, multiple drug findings, and the use of cannabis. Poisonings caused by mAMP abuse were associated with age under 30 years, non-Spanish nationality, palpitations, and single-drug use

Amphetamine and methamphetamine poisonings attended in hospital emergency departments: clinical features and the usefulness of laboratory confirmation. / Intoxicaciones por anfetamina y metanfetamina atendidas en los servicios de urgencias: características clínicas y utilidad de la confirmación analítica.

OBJECTIVES: To determine whether clinical and toxicologic findings differed between cases of amphetamine (AMP) and methamphetamine (mAMP) poisoning attended in 2 Balearic Island hospital emergency departments. MATERIAL AND METHODS: Retrospective observational study of AMP and mAMP cases with laboratory confirmation between 2013 and 2018. We compared clinical and toxicologic variables as well as clinical management between groups. RESULTS: 1) A total of 120 cases were found: 86 (71.7%) with AMP poisoning and 34 (28.3%) with mAMP poisoning. 2) Drug poisoning was confirmed by gas chromatography associated with mass spectrometry (GC-MS) in 787 urine samples found to be positive during screening. One hundred fifty-four (19.6%) were confirmed by GC-MS. Thirtyfour of them did not meet the inclusion criteria. 3) Significant differences between AMP and mAMP cases were found for age (32.3 vs 28.4 y, respectively); sex (72.1% vs 94.1% men); and Spanish nationality (64.0% vs 29.4%). Reasons for admission and clinical features also differed: the reasons were aberrant behavior (15.1% in the AMP group vs 0% in the mAMP group) and palpitations (1.2% vs 20.6%); agitation was observed in 27.9% and 8.8%, respectively. Clinical management was similar in the 2 groups. Multiple drug poisoning was detected in 76.6% patients and was more common in patients in the AMP group (82.6% vs 61.8%). The additional drugs in these cases were mainly cocaine (63.0%), cannabis (48.9%), 3,4-methylenedioxy-N-methamphetamine (MDMA) (38.0%), and alcohol (35.9%). Cannabis was detected in a significantly higher proportion in the AMP group (45.3%) than in the mAMP group (17.6%). False positives were found in 78.7% of the samples. The culprit drug was most often MDMA (71.2%). CONCLUSION: AMP poisonings were associated with age over 30 years, Spanish nationality, aberrant behavior, agitation, multiple drug findings, and the use of cannabis. Poisonings caused by mAMP abuse were associated with age under 30 years, non-Spanish nationality, palpitations, and single-drug use.

OBJETIVO: Investigar si existen diferencias clínicas y toxicológicas en pacientes intoxicados por anfetamina (ANF) y metanfetamina (MANF) atendidos en servicios de urgencias. METODO: Estudio observacional retrospectivo de intoxicaciones por ANF y MANF con confirmación analítica en Baleares (2013-2018). Se compararon variables clínicas, toxicológicas y de manejo clínico entre grupos. RESULTADOS: 1) Se incluyeron 120 pacientes, 86 (71,7%) grupo ANF y 34 (28,3%) grupo MANF. 2) La confirmación de derivados anfetamínicos se realizó por cromatografía de gases-espectrometría de masas en 787 muestras de orina previamente positivas mediante un método de cribado cualitativo. Se confirmaron 154 (19,6%) muestras. De ellas, 34 fueron excluidas. 3) Se encontraron diferencias significativas entre ANF y MANF en: edad (32,3 vs 28,4 años); sexo (72,1 vs 94,1% hombres); nacionalidad española (64,0 vs 29,4%); en motivos de admisión: alteración de conducta (15,1 vs 0%) y palpitaciones (1,2 vs 20,6%); y en características clínicas: agitación (27,9 vs 8,8%). No hubo diferencias de manejo clínico. El 76,6% de casos fueron polintoxicaciones, más comunes en ANF (82,6 vs 61,8%). En estos casos se detectó principalmente cocaína (63,0%), cannabis (48,9%), MDMA (38,0%) y alcohol (35,9%). La mayor asociación del cannabis con el grupo de ANF fue estadísticamente significativa (45,3 vs 17,6%). La causa de los falsos positivos se identificó en el 78,7% de muestras, siendo el MDMA (71,2%) la principal. CONCLUSIONES: Se observaron diferencias entre ANF y MANF en cuanto a variables demográficas y motivo de asistencia; no obstante en esta serie hubo un alto porcentaje de polintoxicaciones.

Identificación de líquidos biológicos de origen desconocido / Identification of body fluids of unknown origin

Los laboratorios clínicos son frecuentemente requeridos para la identificación de líquidos corporales de los que se desconoce su origen. La información bibliográfica con respecto a la identificación de líquidos biológicos de procedencia incierta es escasa. El objetivo de este documento es actualizar los conocimientos sobre aquellos constituyentes útiles como marcadores para la identificación y diferenciación de estos líquidos. Se abordan aspectos como la identificación de una punción lumbar traumática o de líquido cefalorraquídeo en fístulas, la identificación de un derrame quiloso o pseudoquiloso, de secreción biliar, pancreática, gastroesofágica o de orina en las cavidades serosas así como del líquido amniótico

Clinical laboratories are regularly requested to analyze unusual body fluids of unknown origin. There is little in the literature about the identification of body fluids of uncertain origin. The purpose of this document is to perform an updated review on those constituents that may be useful as markers for identifying and diferentiating these unusual fluids. A review is presented on aspects such as the identification of a traumatic lumbar puncture or a cerebrospinal fluid leakage, the identification of a chylous or pseudochylous effusion, leakage of bile, pancreatic fluid, gastroesophageal fluid, or urine, in the serous cavities, as well as the amniotic fluid

Human papillomavirus genotyping in histological sections of precursor lesions of cervical carcinoma: its role as a possible adjunct for the evaluation of the oncogenic potential of specific human papillomavirus genotypes - a study in a coastal region of southeastern Spain.

BACKGROUND: Human papillomavirus (HPV) genotyping is usually performed on cytological specimens with the aim of discerning between high- and low-risk genotypes. METHODS: Paraffin-embedded sections (n = 241) comprising 16 normal/benign (N/B) cervical sections, 72 low-grade squamous intraepithelial lesions (LSIL), 133 high-grade SIL (HSIL), 6 invasive carcinomas (cervical cancer), and 14 atypical immature metaplasias (AIMs) were DNA extracted and HPV genotyped. RESULTS: The most frequent HPV genotypes found were 16 and 58. HPV16 was detected in 0% N/B, 18.1% LSIL, 42.9% HSIL (p < 0.001), 50% carcinoma, and 35.7% AIM, whilst HPV58 was detected in 25.0, 20.8, 16.5, 0 and 35.7% of these lesions, respectively. DISCUSSION: The high prevalence of HPV58 and the low prevalence of HPV18 suggest the limited effectiveness of HPV vaccination in southeast Spain (prevention of 45.1% HSILs). The HPV genotype distribution profile in AIM suggests that these lesions are more similar to LSIL than HSIL pointing to a low risk of progression to cervical cancer. These results reinforce the necessity of assessing the specific genotype rather than distinguishing between high- or low-risk HPV. The use of histological section instead of cytological specimens for specific HPV genotyping would be very useful in order to ascertain the oncogenic potential of each of the genotypes found in a given area.

Effect of human papillomavirus on cell cycle-related proteins p16, Ki-67, Cyclin D1, p53, and ProEx C in precursor lesions of cervical carcinoma: a tissue microarray study.

In-depth study of cell cycle proteins and human papillomavirus (HPV) genotyping can provide useful information about the malignant potential of precursor lesions of cervical carcinoma (CC). Immunostaining of cell cycle-related proteins (p16, cyclin D1, Ki-67, p53, and ProEx C) was evaluated using tissue microarrays, and HPV genotypes were identified in 144 cervical tissue specimens encompassing normal or benign epithelial lesions, low- and high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively), and CC. In addition, 14 cases with atypical immature metaplasia (AIM) were included to compare their immunohistochemical features with those of well-established precursor lesions. Expression of p16, Ki-67, and ProEx C was most associated with the severity of dysplasia. Positive expression of p16, Ki-67, and ProEx C and negative expression of p53 seem to be related to HPV-16 infection. AIM cases show an immunohistochemical pattern more similar to LSIL than to HSIL. Immunohistochemical assessment of cell cycle proteins may help to distinguish normal and benign conditions of the cervix from precursor lesions of CC.