The immunohistology of follicle lysis in lymph node biopsies from homosexual men

Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis.     

Cytomegalovirus associated oral ulcerations in HIV-infected patients

Oral ulcerations associated with disseminated cytomegalovirus (CMV) infection were observed in four patients with AIDS manifestations showing low CD4 counts. Virus cultures of urine and saliva samples were positive for CMV in all cases. The lesions were characterized by a punched-out appearance, non-indurated borders, low bleeding tendency and lack of inflammatory wall. Light microscopy revealed granulation tissue containing "owl's eye" like cells in all specimens. Presence of CMV was confirmed by immunohistochemistry and in situ hybridization. The ulcerations were infiltrated with T-lymphocytes of the helper, suppressor and cytotoxic subset, most were positive for HLA DR. Despite the local invasion with immunocytes and high serum titers of serum antibodies the patients experienced progressive CMV disease.     

Full thickness squamous atypia of the glans penis on a background of Zoon's plasma cell balanitis

Erythroplasia of Queyrat (EQ) or squamous cell carcinoma in situ of the glans penis developed in a 79 year old uncircumsised gentleman who had a six year prior history of biopsy proven Zoon's plasma cell balanitis (ZB) affecting the same site on the glans. Prior to the development of clinically evident EQ, the glans had been treated with topical pimecrolimus 1% for one month. The glans was subsequently treated with topical 5-flourouracil 5% for two weeks which resulted in clinical clearance.
EQ is obviously an important differential for penile plaques because of the potential for progression to squamous cell carcinoma, while ZB is generally regarded as benign. The differentiation can only be reliably made histologically.
There are other case reports of both EQ ( 1 ) and carcinoma of the penis ( 2 ) arising in patients with ZB, raising the question as to whether ZB may actually reflect a reaction to underlying pre-existing pathology or even a premalignant state.
The addition of topical pimecrolimus shortly before EQ became clinically evident in this patient is concerning in the light of recent concern regarding the carcinogenicity of topical calcineurin inhibitors ( 3 ).
This case highlights the importance of close clinical follow up of persistent penile inflammatory lesions and prompt biopsy of clinically suspicious areas as second and potentially more serious pathology may occur concomitantly.