An algorithm for the treatment of type 2 diabetes in Latin America

Diabetes is a principal and growing health concern in Latin America, accounting for significant mortality and morbidities. Large, randomized, prospective trials of various interventional therapies in patients with both type 1 and type 2 diabetes have demonstrated that reductions in hyperglycaemia and management of diabetes-related risk factors can significantly reduce the micro- and macrovascular complications of diabetes. Therefore, patients with type 2 diabetes will benefit from more aggressive treatment regimens to help decrease the occurrence and rate of progression of diabetic complications. Given the many complexities of diabetes management, it is often difficult for general practice physicians to stay abreast of emerging treatment strategies and therapies. Owing to the high prevalence of type 2 diabetes in Latin America, the majority of patients with diabetes are treated by generalists rather than specialists. This article was intended to assist physicians and other healthcare professionals in developing and using effective treatment strategies to stem the growing epidemic of diabetes and its complications in Latin America.

Neuroblastoma: changing incidence and survival in young people aged 0-24 years. A report from the North of England Young Persons' Malignant Disease Registry

BACKGROUND AND PROCEDURE

Population based data for neuroblastoma in children and young adults under 25 years at diagnosis were ascertained from the Northern Region Young Persons' Malignant Disease Registry for the period 1968-1995. Age-standardised incidence rates were calculated (ASR) and changes in incidence and survival were investigated. Over the study period 144 patients were registered, of these 136 were children under 15 years at diagnosis (median age: 2.2 years, ASR: 8.6 cases per million children per year), and 8 were 15-24 years (ASR 0.6).

RESULTS AND CONCLUSIONS

Incidence of childhood neuroblastoma in the North of England increased significantly over time; ASRs were 5.8 for 1968-1981 and 9.5 for 1982-1995 (rate ratio: 1.6, 95%; CI 1.2-2.3). The increase in incidence was seen in both infants and older children, and in both low stage and advanced disease. Overall 5 year survival was 15% for 1968-1981 and 40% for 1982-1995 (P < 0.0001). Significant improvements in survival were documented across different stage and age-groups, including those over 1 with stage 4 disease (0% versus 18%, P < 0.0001). Further research is needed to investigate the reasons for the increasing incidence of neuroblastoma.

Incidence and survival for cancer in children and young adults in the North of England, 1968-1995: a report from the Northern Region Young Persons' Malignant Disease Registry

The Northern Region Young Persons' Malignant Disease Registry records information on young people under 25 years old diagnosed with cancer in the Northern Region of England. Incidence and survival rates were calculated for children and young adults diagnosed with cancer between 1968 and 1995. There were 2099 (M:F 1.28:1) children (age 0-14 years) and 2217 (M:F 1.23:1) young adults (15-24 years) diagnosed with a first cancer between 1968 and 1995. The age-standardized rate (ASR) for childhood cancer was 121 per million 0 to 14 year-olds per year. For young adults the ASR was 175 per million 15 to 24 year-olds, per year. Incidence of childhood cancer increased over time at a rate of 12 extra cases per million children, per decade (P < 0.001). In young adults incidence rates increased by 16 extra cases per million 15 to 24 year-olds, per decade (P < 0.001). For childhood cancer 5-year survival was 42% for those diagnosed 1968-1977, 57% for 1978-1987 and 71% (95% CI 67-75) for 1988-1995. Survival for young adults over the three periods was 45%, 62% and 73% (95% CI 70-78) respectively. The cumulative risk of developing cancer before the age of 25 is 1 in 285. Over the 28-year period there were significant improvements in survival and modest increases in incidence in both children and young adults.

Drawing specimens for coagulation testing: is a second tube necessary?

Three recent studies discussed the possibility that the National Committee for Clinical Laboratory Standards (NCCLS) recommendations that the coagulation specimen should be the second or third tube collected are unnecessary. However, only one reagent/instrument was used in each study. Our protocol differed from the previous studies because we performed the assays on three different reagent/instrument systems on the same samples. Our study used photo-optic, mechanical, and nephelometric systems of clot detection. After obtaining informed consent, we obtained two blue-stoppered tubes of blood from 95 subjects: 15 normal patients and 80 patients currently on coumadin therapy. No discard tube was drawn for coagulation testing. A prothrombin time with an international normalized ratio and an activated partial thromboplastin time, were performed on each tube. Laboratory One used a MLA 1600C (Hemoliance) with Thromboplastin DS (Pacific-Hemostasis, ISI of 1.11) and APTT-LS (Pacific-Hemostasis). Laboratory Two used an STA (Diagnostica-Stago) with Neoplastine CI+ (Diagnostica-Stago, ISI of 1.14) and PTT-LT (Diagnostica-Stago). Laboratory Three used an ACL 300 with Plastinex (Biodata, ISI of 1.67) and Actin FSL (Dade Behring). No clinical or statistically significant differences were seen between the first or second tubes on any of the three reagent/instrument combinations in the PT in seconds, international normalized ratio reporting, or APTT results. Our results indicate that the NCCLS guidelines for obtaining a second tube when performing coagulation testing should be considered for elimination when new revisions are published.

Hepatobiliary cystadenoma with mesenchymal stroma: expression of oestrogen receptors in formalin-fixed tissue

We report three cases of hepatobiliary cystadenoma with mesenchymal stroma in which oestrogen receptor immunostaining was carried out, after using a microwave method of antigen retrieval. In one of the tumours immunoreactivity for oestrogen receptors was demonstrated within the mesenchymal stromal cells. The presence of oestrogen receptors supports the theory that oestrogens act as tumour promoters and may explain the female predilection.

Immunohistochemical study of tissue factor expression in normal intestine and idiopathic inflammatory bowel disease

AIMS

To investigate the localisation of tissue factor expression in normal and inflamed intestine.

METHODS

Serial cryostat sections of tissue taken from patients with Crohn's disease (n = 8), ulcerative colitis (n = 5), and from controls (n = 5) were stained with haematoxylin and eosin and immunostained for tissue factor, collagen type IV, fibrinogen and platelet glycoprotein IIIa.

RESULTS

In control tissues tissue factor was present as a continuous layer along the epithelial basal lamina: sections from controls did not immunostain for fibrinogen or platelets. In non-ulcerated inflamed mucosa, tissue factor staining intensified in cases of Crohn's disease and was associated with fibrin deposition. Staining for tissue factor was either patchy or absent in cases of ulcerative colitis and there was no fibrin deposition. This change accompanied the early destruction of the epithelial basal lamina in ulcerative colitis that was not seen in Crohn's disease. In both diseases tissue factor expression in severely inflamed and ulcerated mucosa was present on lamina propria macrophages and vascular endothelium and was associated with fibrin or platelet thrombi. In three of eight cases of Crohn's disease tissue factor expression and thrombi were evident in areas of submucosal vasculitis. These were not seen in adjacent normal vessels.

CONCLUSIONS

These observations are consistent with a tissue factor haemostatic barrier in the intestine: this barrier seems to be incomplete or defective in ulcerative colitis. Tissue factor expression by macrophages and endothelial cells may be important, particularly in the microvascular thrombosis and induration which are characteristic of Crohn's disease.

Pulmonary platelet aggregates: possible cause of sudden peroperative death in adults undergoing liver transplantation

AIMS

To determine if massive pulmonary platelet thromboembolism is a common cause of peroperative death following liver transplantation; and to compare the incidence of this event with patients dying after non-transplantation procedures.

METHODS

Necropsy tissues from all patients dying within 10 days of operation during the past three and a half years were studied (six liver transplantations and 13 unrelated operations). Haematoxylin and eosin stained sections of all tissues were examined. Additional sections of lung tissue were immunostained for constituents of thrombus (fibrin and platelets).

RESULTS

At necropsy the lungs from all six liver transplant recipients were heavy with a rubbery texture and little oedema fluid. Those from non-transplantation patients appeared normal or very oedematous. Microscopic examination showed that there were numerous platelet aggregates occluding pulmonary capillaries in all six transplant recipients, but in only three of the non-transplant patients. These thrombi were numerous in patients dying during surgery and the number was underestimated in routine sections because of the surrounding capillary congestion. Detection was improved by immunostaining for platelets with factor XIIIA and platelet glyco-protein IIIa.

CONCLUSIONS

Massive platelet thromboembolism is a likely cause of death in patients dying unexpectedly following recent liver transplantation. Non-transplantation patients dying during surgery who show similar appearances usually have conditions known to have a high risk of thrombosis or embolism (cement hypotension syndrome and disseminated intravascular coagulation). The cause of this extensive platelet activation in liver transplant recipients is uncertain and may be multifactorial. The unusual rubbery consistency of the lungs on macroscopic examination could alert the pathologist to the underlying condition. Immunostaining for platelets improves the detection microscopically.

Early mucosal changes in Crohn's disease

Aphthoid ulceration has been regarded as an early macroscopic feature of Crohn's disease, yet the cause of this mucosal lesion is unknown. Examination of areas of apparently normal and non-inflamed bowel in Crohn's disease has allowed the identification of mucosal changes which occur before macroscopic and microscopic ulceration. Thirty five resection specimens from patients with Crohn's disease were compared with 12 specimens from patients with ulcerative colitis and 13 controls. Specimens were fixed either by immersion in formalin in the routine way or by perfusion fixation with formalin at mean arterial pressure. Immunostaining for macrophages, vessel wall, and blood constituents allowed identification of small mucosal capillaries which were not apparent otherwise. In Crohn's disease damage and rupture of these small capillaries occurred before infiltration of the lamina propria by inflammatory cells. Loss of the overlying epithelium seemed to follow this vascular damage.

Factor XIIIA subunit and Crohn's disease

Factor XIIIA is the active subunit of plasma factor XIII that is responsible for cross linking fibrin into a stable clot. Sixteen patients with Crohn's disease were studied prospectively from relapse (Crohn's disease activity index > 150) into remission. Plasma factor XIIIA concentrations were significantly lower in active disease (median 63 (95% CI 46-72) U/dl) than remission (median 90 (95% CI 60-112) U/dl; p = 0.002). Plasma factor XIIIA concentrations correlated positively with the activity index (p = 0.005) and platelet count (p = 0.003), and negatively with serum albumin (p = 0.006). In five patients with persistent aggressive disease, the factor XIIIA concentration remained below the lower range of normal despite apparent clinical improvement in response to medical treatment. Tissues from three patients who underwent surgical resection during the study were immunostained for factor XIIIA. Gut mucosal and submucosal macrophages stained strongly for factor XIIIA. In one patient, capillary thrombi near superficial mucosal erosions immunostained for factor XIIIA in macroscopically normal mucosa. Similar changes were identified in more severely inflamed sections of intestine from the other two patients. The demonstration of significantly low plasma factor XIIIA concentrations in active Crohn's disease, and the immunostaining of factor XIIIA in capillary thrombi in the bowel wall, suggest that activation of coagulation may be involved in the pathogenesis of Crohn's disease. The plasma factor XIIIA concentration may prove a useful laboratory marker of disease activity.

Mast cells in the female genital tract

Mast cells in the human uterus and adnexa have been studied using basic lead acetate fixation and a long toluidine-blue technique to maximise the numbers of cells stained. Counts were performed on measured areas of tissue and the numbers of mast cells related to clinical and pathologic variables. Considerable variation in numbers was found among individual cases at all the sites studied. In the endometrium and myometrium, a drop in the number of mast cells has been demonstrated with advancing age, particularly after menopause. In leiomyomas the highest counts were in the smaller and more cellular lesions. It is concluded that the numbers of mast cells are at least partly related to the degree of cellularity or atrophy of the surrounding tissues. No significant association was found with menorrhagia or with the presence of leiomyomas.

QBEnd/10: a new immunostain for the routine diagnosis of Kaposi's sarcoma

Kaposi's sarcomas are seen more commonly in routine histopathology laboratories since the advent of the more widespread and aggressive variant of the disease associated with HIV infection. Distinguishing nodular lesions from other spindle cell and vascular tumours can sometimes be difficult. Immunohistochemistry has been disappointing as a diagnostic aid, often requiring special fixation or frozen tissue and even then, staining of spindle cells has been variable. We describe the use of the new IgG1 mouse monoclonal antibody raised against human placental endothelial cells, QBEnd/10, on routine formalin-fixed, paraffin-embedded tissue. A retrospective study was performed on 22 Kaposi's sarcomas of skin including patch, plaque, and nodular lesions and compared with 38 other vascular and spindle cell tumours from skin. All sections were stained with haematoxylin and eosin, QBEnd/10, Ulex europaeus agglutinin 1 (UEA-1) and for factor VIII-related antigen (FVIIIRAg). The results demonstrate that spindle cells in lesions from Kaposi's sarcomas, but not other vascular or spindle cell tumours, immunostain clearly with QBEnd/10. Immunostaining for FVIIIRAg shows only weak and irregular positivity of the spindle cells, whilst staining with UEA-1 is consistently negative. We find that immunostaining with QBEnd/10 aids the diagnosis of Kaposi's sarcomas and allows their distinction from other spindle cell neoplasms of skin in routinely processed material.

The mast cells of the human uterus

Staining of mast cells in the human uterus has been studied using four fixatives and five staining methods to determine whether there are subpopulations of mucosal (endometrial) and connective tissue (myometrial) mast cells, and to discover how they can best be demonstrated. Following formalin fixation none of the staining methods showed maximum staining of mast cells in either endometrium or myometrium. The best demonstration of uterine mast cells is by fixation with either isotonic formol acetic acid or Mota's basic lead acetate followed by staining with the long toluidine blue technique. Although the degree of MC understaining following formalin fixation was greater for the endometrium than for the myometrium this is inadequate evidence to designate two cell populations. The findings suggest that the mast cells of the human uterus are all one population but show heterogeneity of histological properties possibly related to their functional state.