Interobserver variation in classifying lymphomas among hematopathologists.

BACKGROUND: Lymphomas are common malignancies that have various subtypes with many overlapping histologic, immunophenotypic and genetic features. Therefore, discordance in classifying lymphoma among pathologists may be encountered. But this issue is not well characterized. We conducted the present study to demonstrate discordances among Thai hematopathologists as well as to highlight common arguing points for classifying lymphomas. METHODS: The 117 lymphoma cases were randomly retrieved and individually reviewed by 7 hematopathologists, members of the "Thai Hematopathologist Group," without knowing the original diagnoses. The consensus diagnoses were given from a discussion by all members. In each case, the diagnosis from each participant was compared with the consensus diagnosis and classified into 4 categories as follow: 1) concordance, 2) minor discordance, 3) major discordance and 4) serious discordance. RESULTS: There were approximately 11% discordances between original and consensus diagnoses. The average discordances among all pathologists according to minor, major and serious discordances were 10%, 3.5% and 0.3%, respectively. Diffuse large B-cell lymphoma had the least discordance (7%). Small biopsies had been found to increase discordances in some lymphoma subtypes. CONCLUSIONS: The present study reveals some degrees of interobserver variation in classifying of lymphoma by using the 2008 WHO classification among hematopathologists. Some types of lymphomas on small biopsies were found to have a significant higher discordance rate. This study also described some common diagnostic discordances regarded as potential pitfalls in classifying lymphomas. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_162.

Relationship of cell bearing EBER and p24 antigens in biopsy-proven lymphocytic interstitial pneumonia in HIV-1 subtype E infected children.

Lymphocytic interstitial pneumonia (LIP) is an uncommon histopathologic entity characterized by infiltration of the interstitium and alveolar spaces of the lung by lymphocytes and other lymphoid elements. An increased incidence of LIP has been seen in the pediatric population, especially in children with acquired immune deficiency syndrome. Our previous study supports the notion that Langerhans cells (LCs) are reservoirs for Epstein-Barr virus (EBV) in lungs of human immunodeficiency virus (HIV) subtype E-infected pediatric LIP. To further understand the pathogenesis of LIP, we studied the relationship between EBV, the suggested causative agent of LIP and HIV-1 capsid protein p24, which play an important role in the interaction with host proteins during HIV-1 adsorption, membrane fusion, and entry in surgical lung biopsy-proven LIP from 9 vertically HIV subtype E-infected pediatric patients. The dominant microscopic feature of LIP demonstrated widespread widening of alveolar septum by mononuclear inflammatory cell infiltrate, mainly composed of mature lymphocytes and plasma cells surrounding airways and expanding to the lung interstitium. EBV-encoded RNA (EBER) in situ hybridization (ISH) and p24 immunohistochemistry, performed on formalin-fixed, paraffin-embedded tissue from open lung biopsy specimens, revealed positive intranuclear EBER signals and intracytoplasmic immunostains for p24 core protein in all 9 LIP cases. By combining ISH and immunohistochemistry, these results suggest that (i) EBV/p24-carrying cells are likely involved in the development of LIP, either directly or indirectly; (ii) LCs and related dendritic cells are the main reservoir of both EBV and HIV subtype E in pediatric LIP and possibly LCs may play an important role in the recruitment of inflammatory cell infiltrates, especially T cells into these tissues; (iii) coexpression of EBV/p24 in bronchioalveolar epithelium supports the hypothesis that these cells serve as a reactivation source for both viruses to achieve greater quantities in alveolar septum and interstitium around bronchioles. These results indicate a strong association between the presence of HIV core protein p24 and expression of EBV RNA transcripts (EBER). Interactions between LCs and related dendritic cells together with T cells are important for effective HIV and EBV replications. The coexpression of both viruses could be related to the evolution of pediatric LIP in HIV subtype E infection.

Hepatoprotective effects of lychee (Litchi chinensis Sonn.): a combination of antioxidant and anti-apoptotic activities.

AIM OF THE STUDY: Gimjeng and Chakapat lychee (Litchi chinensis Sonn.) were evaluated for hepatoprotective activity on CCl(4)-induced hepatotoxicity in rats. MATERIALS AND METHODS: Fruit pulp extracts of the lychees were examined for vitamin C, phenolic contents, anti-lipid peroxidation activity and hepatoprotective effect. Male Wistar albino rats were intraperitoneally injected (ip) with CCl(4) (2 ml/kg), then were orally administered (po) with silymarin (100mg/kg), and Gimjeng or Chakapat extracts (100 and 500 mg/kg). After ten days, the rats were sacrificed and their livers were examined histopathologically and immunohistochemically. Their serum glutamate-pyruvate transaminase, glutamate-oxalate transaminase, and alkaline phosphatase activities were analyzed. Apoptotic activity of the livers was assessed quantitatively. RESULTS: The Gimjeng and Chakapat extracts showed the contents of vitamin C (1.2±0.6 and 4.3±0.1mg/100g) and phenolics like trans-cinnamic acid and pelargonidin-3-O-glucoside (9.80±0.21 and 19.56±0.4 mg GAE/g extract, respectively), and trolox equivalent antioxidant capacity (TEAC) values (11.64 and 9.09 g/mg trolox), respectively. The Gimjeng as compared to the Chakapat demonstrated a better antioxidant activity as revealed by anti-lipid peroxidation activity with the TEAC values. Administration of CCl(4) in rats elevated the serum GPT, GOT, and ALP level whereas silymarin, Gimjeng and Chakapat extracts prevented these increases significantly. Significant decrease of apoptotic cells together with restoration of morphological changes confirmed the hepatoprotective effect in the CCl(4)-induced rats pretreated with the extracts. CONCLUSION: Antioxidant properties of the Gimjeng and Chakapat lychees as evidenced by the vitamin C and phenolic compounds, anti-lipid peroxidation and anti-apoptosis could explain the hepatoprotective effects in CCl(4)-induced hepatotoxicity.

Cell reservoirs of the Epstein-Barr virus in biopsy-proven lymphocytic interstitial pneumonitis in HIV-1 subtype E infected children: identification by combined in situ hybridization and immunohistochemistry.

Lymphoid interstitial pneumonitis (LIP), a frequent pulmonary complication in human immune deficiency virus (HIV)-infected pediatric patients, is characterized histologically by marked infiltration of lymphoid cells. Several theories have been suggested that LIP may be caused by Epstein-Barr virus (EBV). To identify the reservoir of EBV and pathogenesis of lymphoid infiltrates in HIV subtype E infected pediatric LIP, we examined the distribution and expression of EBV in the inflammatory cell recruitment in surgical lung biopsy-proven LIP from 9 vertically HIV subtype E-infected pediatric patients. The dominant microscopic feature of LIP demonstrated widespread widening of alveolar septum by mononuclear inflammatory cell infiltrate mainly composed of mature lymphocytes and plasma cells surrounding airways and expanding to the lung interstitium. EBV-encoded RNA (EBER) in situ hybridization, performed from paraffin-embedded lung tissues, revealed positive intranuclear signals in all 9 LIP cases. Interestingly, combined immunohistochemical and in situ hybridization analyses in 6 out of 9 LIP cases revealed 30% to 50% of the Langerhans and related dendritic cells were infected with EBV, whereas <30% of the T and B cells were infected with EBV. These results suggested that a chronic antigenic stimulus of EBV played important roles in the pathogenesis of LIP in these patients. This supports the notion that Langerhans cells (LCs) are more readily infected with EBV, indicating that LCs are reservoirs for EBV in lungs of HIV subtype E-infected pediatric LIP. And possibly LCs may play an important role in the recruitment of inflammatory cell infiltrates, especially T cells into these tissues. In addition, HIV may provide a milieu or microenvironment for the evolution of LIP, which represent an immunologic response to EBV infection. Interactions between LCs and related dendritic cells together with T cells are important for effective HIV and EBV replications.

Cell reservoirs in lymph nodes infected with HIV-1 subtype E differ from subtype B: identification by combined in situ polymerase chain reaction and immunohistochemistry.

In Thailand, the predominant HIV subtype is E, rather than subtype B as in North America and Europe. Subtype E has the ability to replicate in vitro in Langerhans cells. We hypothesized that this cell type might constitute a reservoir for the HIV virus in infected lymph nodes. We examined lymph nodes from 25 HIV-1 subtype E-infected patients to determine the immunophenotype of HIV-1-infected cells, their numbers and their distribution. The presence of HIV was detected either by in situ reverse transcriptase-polymerase chain reaction or immunoperoxidase. Cell identity was determined by double labelling using alkaline phosphatase-based immunohistochemistry. The majority of HIV-infected cells in the lymph nodes were Langerhans cells (CD1a+S100+) and Langerhans-related dendritic cells (p55+S100+). These cells were located in the paracortical areas of lymph nodes, with a few cells scattered at the edges of germinal centers, but were absent from germinal centers themselves, in contrast to the reported distribution of subtype B virus. In addition, multinucleated giant cells were significantly more common in HIV-infected nodes (64%) compared to controls (4%) (P=0.00002). In conclusion, Langerhans histiocytes and related cells are reservoirs for HIV subtype E in lymph nodes. Disrupting the pathway of infection of Langerhans cells and related cells may be a viable strategy to interfere with transmission of HIV subtype E.

Effectiveness of short-term and long-term zidovudine prophylaxis on detection of HIV-1 subtype E in human placenta and vertical transmission.

Antiretroviral treatment with zidovudine (ZDV) from the 14th week until the end of pregnancy has markedly reduced the vertical transmission rate of HIV-1 in Europe and North America. A shorter duration of treatment has reduced this rate in Africa and Southeast Asia to a lesser degree. In Southeast Asia, subtype E is the major subtype rather than subtype B as in Western countries. The goals of this study were to determine the optimal duration of ZDV prophylaxis for subtype E and to confirm its effectiveness at the histologic level. Fifty pregnant women seropositive for HIV-1 subtype E were given ZDV prophylaxis consisting of 300 mg administered twice daily, switching to 300 mg administered every 3 hours from the onset of labor until delivery. Twenty-seven received "short-term" ZDV lasting 14 to 35 days before delivery, whereas the other 23 received "long-term" ZDV lasting 62 to 92 days. The effectiveness of ZDV prophylaxis was assessed by detection of HIV-1 in the placenta using in situ polymerase chain reaction (PCR). All babies in this study were tested up to one year of age. Three were not positive until after one month of age, but one was positive as a neonate. Four neonates were positive for HIV-1 as detected by PCR on peripheral blood, including one in the neonatal period. All cases were from the short-term prophylaxis group. Decidual glandular epithelial cells were the only cell type in the placenta that expressed HIV proviral DNA under ZDV prophylaxis. Sixty-seven percent of placentas in the short-term ZDV group showed more than occasional positive cells compared with 22% in the group receiving long-term ZDV prophylaxis (P < 0.02). This is first study to compare the effectiveness of short-term and long-term ZDV prophylaxis with respect to the presence of HIV in the placenta. Our study shows that longer (at least 60 days) prophylaxis is more effective in reducing HIV expression in the placenta and is associated with reduced transmission to neonates.

Why were limbs amputated? An evaluation of 216 surgical specimens from Chiang Mai University Hospital, Thailand.

INTRODUCTION: Limb loss has a devastating effect on patients. To know the underlying causes of limb amputation would be helpful in planning public health strategies in the country. The objectives of this study are (1) to identify the primary causes and the feature of limb amputations in the setting of a university hospital, and (2) to study the time trends of the causes of limb amputation over a period of 5 years. MATERIALS AND METHODS: The clinical and pathological data from 216 amputated limbs submitted to the Pathology Department of Chiang Mai University Hospital from 2000 to 2004 were reviewed. RESULTS: Of these, 188 cases were first time amputations, and 28 cases were repeat amputations. The 188 first amputated specimens included 23 upper limbs (12%) and 165 lower limbs (88%), from 115 male (61%) and 73 female (39%) patients. Dysvascular (46%), tumor-related (36%), and infection-related (10%) amputations were the three most common scenarios. The rate of amputation was high in 2004 (32%) owing to an unexpected increase in the numbers of dysvascular amputation. Atherosclerosis accounted for at least 52% of dysvascular amputations. The leading cause of tumor-related amputations was sarcoma (72%), almost half of which were osteosarcomas. The major cause of lower limb amputation was dysvascular (51%) whereas that of upper limb amputation was tumor related (61%). Subgroup analysis of the major limb amputations revealed that 44% were tumor related, 39% were dysvascular, and 8% were infection-related causes. The proportion of major limb losses in the tumor-related group (87%, 59/68) was significantly higher than those in the dysvascular group (62%, 53/86) (P = 0.001). In addition, the proportion of upper limb losses in the tumor-related group (21%, 14/68) was significantly greater than those in the dysvascular group (2%, 2/86), (P < 0.001). The causes of 28 repeat amputations were similar, i.e., dysvascular (61%), tumor related (29%), and infectious related (7%). CONCLUSION: (1) Atherosclerosis, a potentially preventable disease is responsible for the great proportion of limb losses in Northern Thailand; (2) the numbers of dysvascular amputation seem to be increasing; (3) tumor, especially sarcoma, is the most common cause of major limb amputations as well as upper limb loss.

Chorioamnionitis is associated with placental transmission of human immunodeficiency virus-1 subtype E in the early gestational period.

The frequency and the cellular basis for HIV-1 transmission from mother to child in the early gestational period are poorly understood. We compared the placentas of 24 women seropositive for HIV-1 subtype E and who had not received any antiretroviral drugs, to placentas of 25 seronegative women. All placentas were obtained during therapeutic abortion at 6-23 weeks gestation. Placentas and fetal organs were examined by routine light microscopy, immunostaining for p24 capsid protein, and in situ PCR to localize which cells were infected with HIV-1 subtype E. The number of previous abortions was not a factor in placental HIV infection since this number was higher in seronegative women (P < 0.01). There were no significant differences between the placentas of the two groups with respect to presence of chorioamnionitis, villitis, villous stromal fibrosis, infarction, abnormal villous maturation, deciduitis or decidual necrosis. HIV-1 subtype E was detected in up to 83% of placentas, either by immunostaining or in situ PCR, in trophoblast, villous stromal cells, Hofbauer cells, decidual and decidual glandular epithelium. Fetal organs were positive for HIV in 30% (6/20) of cases. There was a significant association between transmission of HIV to the fetus and the histologic findings of chorioamnionitis, plasmacellular deciduitis and decidual cell necrosis. This is the first report showing an association of chorioamnionitis with early in utero transmission of HIV-1 subtype E. This may help explain the cases of in utero transmission that persist despite antiretroviral prophylaxis, given that therapy is started in the late gestational period.

Kaposi's sarcoma in rheumatic diseases.

OBJECTIVE: To review the clinical features and outcome of all reported cases of Kaposi's sarcoma in patients with rheumatic diseases. METHODS: In addition to our patient, we identified cases from a Medline search between the years 1966 and 2002. Cases associated with human immunodeficiency virus infection were excluded. RESULTS: Including our patient, there were a total of 25 cases reported (11 men and 14 women). Rheumatoid arthritis was present in 8 cases, polymyositis/dermatomyositis in 5, vasculitis syndromes in 5, systemic lupus erythematosus in 3, polymyalgia rheumatica in 2, and 1 each of undifferentiated connective tissue disease and Behcet disease. All but 1 patient had been given systemic corticosteroids for a duration that ranged from 6 weeks to 22 years, and immunosuppressive drugs from 25 days to 3.5 years. The Kaposi's lesions usually involved the skin on the extremities; internal organ involvement occurred in 7 cases. Most lesions responded to a decreasing dosage of corticosteroids and immunosuppressive drugs, or to the administration of radiation or cytotoxic therapy. Six patients died, 4 of which were related to the progression of Kaposi's sarcoma. CONCLUSION: Kaposi's sarcoma in patients with rheumatologic conditions is rare. The clinical features are similar to those with classical Kaposi's sarcoma. Tumor regression usually occurs with decreasing corticosteroids and/or immunosuppressive drugs, local irradiation, or cytotoxic therapy.