Clinicopathological characteristics of Klinefelter syndrome: a testicular biopsy analysis of 87 cases / 中华病理学杂志

Objective: To investigate the clinicopathological characteristics of testicular biopsies from Klinefelter syndrome (KS) patients. Methods: The testicular biopsy specimens of 87 patients with KS (a total of 107 biopsy specimens) were collected from the Department of Pathology, Peking University Third Hospital, Beijing, China from January 2017 to July 2022. All patients were diagnosed as KS by peripheral blood karyotyping analysis. The testicular histopathologic features, testicular volume and hormone levels were evaluated retrospectively. The histopathologic analysis was used to assess the quantity and morphology of Leydig cells, the spermatogenic state of seminiferous tubules, the thickening of the basement membrane of seminiferous tubules and the changes of stroma. Results: Leydig cell proliferative nodules were seen in 95.3% (102/107) of KS testicular biopsy tissues. The eosinophilic inclusion bodies and lipofuscin in Leydig cells were found in 52.3% (56/107) and 57.9% (62/107) of specimens, respectively. The Sertoli cell only seminiferous tubules and the hyalinized tubules were found in 66.4% (71/107) and 76.6% (82/107) of the examined tissues, respectively. The tubules with complete spermatogenic arrest were found in 15.9% (17/107) of specimens, and 5.6% (6/107) of the specimens showed low spermatogenesis or incomplete spermatogenic arrest. In 85.0% (91/107) of the specimens, increased thick-walled small vessels with hyaline degeneration were identified. Conclusions: The most common features of KS testicular specimens are Leydig cell proliferative nodules, hyaline degeneration of seminiferous tubules and proliferation of thick-walled blood vessels. Testicular biopsy specimens of KS are rare. The pathologists can make a tentative diagnosis of KS based on the histological findings, combined with the ultrasound and laboratory results, which is helpful for further diagnosis and treatment of KS.

Malformación genital: disparador del diagnóstico de variantes severas de síndrome de Klinefelter / Genital malformation: trigger of the diagnosis of severe variants of Klinefelter syndrome

Resumen: Introducción: El síndrome de Klinefelter y sus variantes, como alteración en el número de cromosomas sexuales, se encuentra entre los trastornos del desarrollo sexual. Sus portadores manifiestan hipogonadismo hipergonadotrófico en la pubertad; las variantes severas presentan además problemas neurocognitivos y del lenguaje desde edades tempranas. Objetivo: Describir dos pacientes portadores de mal formación genital con diagnóstico genético de variantes severas de síndrome de Klinefelter; y revisar aspectos clínicos y terapéuticos. Casos Clínicos: Caso 1: Diagnóstico de genitales atípicos al nacer: Falo pequeño y corvo con meato uretral a nivel escrotal y escroto bífido. Sin otra anomalía somática, excepto sutil clinodactilia del 5 dedo. Cariotipo: 49,XXXXY. Al año de vida se reconstruyeron los genitales. Evolucionó con retraso global del desarrollo, principalmente del lenguaje, manejado con estimulación temprana kinésica y fonoaudiológica desde los 2 meses, logró integrarse en un jardín de infantes. Caso 2: Al mes de vida se constató falo pequeño y corvo severo (más de 70°), testículos en bolsa. Cariotipo: 48,XXYY. Al año de vida se corrigió malformación del pene. Evolucionó con retraso global del desarrollo, fundamentalmente en el lenguaje expresivo, y fue manejado con el equipo de estimulación temprana desde los 4 meses, logrando adaptación en un jardín de infantes. Conclusión: Las malformaciones genitales condujeron al diagnóstico de variantes severas de síndrome de Klin efelter, y fueron corregidas alrededor del año de vida. La identificación temprana de estas variantes permitió la intervención del equipo de neuroestimulación, favoreciendo el desarrollo neurocognitivo y la integración social de estos niños.

Abstract: Introduction: Among the disorders of sexual development, Klinefelter syndrome and its variants are classified as an alteration in the number of sex chromosomes. These patients show signs of hypergonadotropic hypogonadism at puberty, however cases of severe variants also present neurocognitive and language problems from an early age. Objective: To describe two patients with genital malformation with genetic diagnosis of severe variants of Klinefelter syndrome, and to review clinical and therapeutic aspects. Clinical Cases: Case 1: Diagnosis of atypical genitalia at birth: Small and curved phallus with the urethral meatus at scrotal level, and bifid scrotum. No other somatic abnormality was observed, except for subtle clinodactyly of the fifth finger. Karyotype: 49, XXXXY. At one year of life, genitalia were reconstructed. The patient presented a global developmental delay, mainly in language, which was managed with early stimulation and speech and language therapy since he was two months old. Finally, he was able to attend kindergarten. Case 2: At one month of life, a small and severe curved phallus (more than 70°) was observed, and testicles were in the scrotum. Karyotype: 48, XXYY. At one year of life, the penile malformation was corrected. The patient presented global developmental delay, mainly in expressive language which was managed with early stimulation since the age of four months, achieving kindergarten attendance. Conclusion: Genital malformations led to the diagno sis of severe variants of Klinefelter syndrome, and were corrected around the year of life. The early identification of these variants allowed the intervention of the neurostimulation team, favoring the neurocognitive development and social integration of these children.

Síndrome de Klinefelter diagnosticado en un adulto a raíz del estudio de infección respiratoria recurrente y masa mediastínica: caso clínico / Thymoma in a patient with klinefelter syndrome: case report

Klinefelter syndrome (47, XXY in most cases) is a frequently underdiagnosed chromosomal anomaly associated with multiple comorbidities in adult life. Patients with Klinefelter syndrome have a higher risk of cancer. Specifically, these patients have a higher risk for mediastinal germ cell tumors. It is estimated that 8% of male patients with mediastinal tumors have Klinefelter. We report a 42-years-old male who suffered recurrent respiratory infections. During the study, a mediastinal mass was found, whose pathological study disclosed a type B thymoma. The patient had a history of infertility, high stature, gynecomastia, obesity with gynecoid distribution of body fat and testicular atrophy. A karyotype was requested (47, XXY), confirming the diagnosis of Klinefelter syndrome.

Síndrome 49, XXXXY: aspectos bucales y abordaje clínico / 49, XXXXY Syndrome: oral aspects and clinical approach

El cariotipo 49 XXXXY, es una forma rara de polisomía, considerada una variante del Síndrome de Klinefelter, descripto en el año 1960, siendo muy escasa la información publicada en la literatura científica en el área de la odontología. Algunas de las características fenotípicas predominantes en este síndrome son: rasgos faciales dismórficos, microcefalia, clinodactilia, retardo mental, hipogonadismo y naomaláis esqueletales, siendo la sinostosis radiolunar la más característica. En el 100 por ciento de los casos se ha descripto retraso motor y del lenguaje y en el 50 a 100 por ciento se pueden observa paladar fisurado, malformaciones genitourinarias, hernia inguinal y defectos óseos. Uno de los aspectos bucales relevantes de los pacientes con este síndrome es la presencia de taurodoncia. El propósito de este trabajo es describir las características bucales, las anomalías dentales y su abordaje clínico en forma ambulatoria, en un paciente de 6 años de edad con síndrome de 49 XXXXY