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Abstract Background Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal (GI) tract which has only been recently described based on their specific immunohistochemistry and the presence of particular KIT-related mutations which potentially make them targets for tyrosine kinase inhibition. Methods Sixty-one patients (29 M; 32 F, median age 60 years; range: 23–86 years) between June 1994 and March 2005, were analyzed from two allied institutions. Patient, tumour, and treatment variables were analyzed to identify factors affecting survival. Results Of the 61 patients, 55 (90%) underwent complete surgical resection of macroscopic disease. The 5-year overall survival (OS) rate in the 61 patients was 88% and the 5-year disease-free survival (DFS) in the 55 cases completely resected was 75%. Univariate analysis revealed that R0 resection was strongly associated with a better OSrate (p < 0.0001). Likewise, univariate analysis also showed high mitotic count of > 10 mitoses/per 50 HPF was a significant variable in worse prognosis for OS (≤ 10 mitoses/per 50 HPF 95% 5-year OS vs. > 10 mitoses/per 50 HPF 74% 5-year OS, respectively; p = 0.013). On subsequent multivariate analysis, only high mitotic count remained as a significant negative prognostic variable for OS (p = 0.029). Among patients resected for cure, there were 8 recurrences during follow-up. The mean time to recurrence was 21 ± 10 months (range: 4–36 months). Univariate analysis revealed that mitotic count of > 10 mitoses per 50 high power fields, intratumoural necrosis, and pathological tumour size (> 10 cm in maximal diameter) significantly correlated with DFS (p = 0.006, 0.002 and 0.02, respectively), with tumour necrosis and high mitotic count remaining as independent predictive variables affecting prognosis on subsequent multivariate analysis. Conclusion Most GISTs are resectable with survival principally dependent upon mitotic count and completeness of resection. Future metabolic and genetic analyses will define the role of and resistance to induction or postoperative adjuvant targeted kinase inhibition therapy.

Background: Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal (GI) tract which has only been recently described based on their specific immunohistochemistry and the presence of particular KIT-related mutations which potentially make them targets for tyrosine kinase inhibition., Methods: Sixty-one patients (29 M; 32 F, median age 60 years; range: 23-86 years) between June 1994 and March 2005, were analyzed from two allied institutions. Patient, tumour, and treatment variables were analyzed to identify factors affecting survival., Results: Of the 61 patients, 55 (90%) underwent complete surgical resection of macroscopic disease. The 5-year overall survival (OS) rate in the 61 patients was 88% and the 5-year disease-free survival (DFS) in the 55 cases completely resected was 75%. Univariate analysis revealed that R0 resection was strongly associated with a better OSrate (p < 0.0001). Likewise, univariate analysis also showed high mitotic count of > 10 mitoses/per 50 HPF was a significant variable in worse prognosis for OS ( 10 mitoses/per 50 HPF 74% 5-year OS, respectively; p = 0.013). On subsequent multivariate analysis, only high mitotic count remained as a significant negative prognostic variable for OS (p = 0.029). Among patients resected for cure, there were 8 recurrences during follow-up. The mean time to recurrence was 21 +/- 10 months (range: 4-36 months). Univariate analysis revealed that mitotic count of > 10 mitoses per 50 high power fields, intratumoural necrosis, and pathological tumour size (> 10 cm in maximal diameter) significantly correlated with DFS (p = 0.006, 0.002 and 0.02, respectively), with tumour necrosis and high mitotic count remaining as independent predictive variables affecting prognosis on subsequent multivariate analysis., Conclusion: Most GISTs are resectable with survival principally dependent upon mitotic count and completeness of resection. Future metabolic and genetic analyses will define the role of and resistance to induction or postoperative adjuvant targeted kinase inhibition therapy.

Leptospiral culture, direct immunofluorescence, and the polymerase chain reaction (PCR) were used to detect leptospiral material in postmortem specimens collected from eight patients who died of leptospirosis. Diagnosis of leptospiral infection was based on clinical summary (premortem) and confirmed by serological analysis and/or culture of leptospires. Leptospiral culture was the least sensitive technique, yielding two isolates (3%) from 65 samples. Both isolates were from the aqueous humour and cerebrospinal fluid of the same patient. Direct immunofluorescence was of intermediate sensitivity for detection of leptospires, confirming the presence of leptospires in 11% (2 of 18) of tissue samples from three patients. PCR analysis was the most sensitive technique for detection of leptospiral material in tissue samples, being positive in 20% (11 of 56) of samples from eight patients. Both samples (cerebellum and liver) positive by immunofluorescence were also positive by PCR. The sensitivity of the PCR assay was 1-10 leptospires ml(-1) sample, and the assay was specific for Leptospira pathogenic species. Multi-system involvement was indicated based on successful amplification of leptospiral DNA from more than one tissue sample, which corroborated with the clinical and pathologic findings. The results suggest that in acute and/or fatal leptospirosis, the pathogenesis of the pathologic features are related to the presence of the organisms in the tissues. In conclusion, PCR combined with serology appears to be a useful tool for diagnosis of leptospirosis and may be invaluable in epidemiological studies.

The epidemiology of Helicobacter pylori infection in Barbadian patients and controls was studied. H. pylori was isolated from biopsies from 50/100 (50%) adult patients undergoing endoscopy for investigation of upper gastrointestinal tract symptoms. Urease was detected in biopsies from 54 patients and gastritis was detected by histology in 71 patients. Serology was performed using a commercial ELISA method. Using an IgG concentration of 10 U/ml as a threshold, antibodies were detected in 78% of 100 patients undergoing endoscopy, 72% of 230 blood donors and 22% of 50 children. The mean antibody concentration was significantly higher in patients (92 U/ml) than in blood donors (49 U/ml) or in children (9.5 U/ml). Culture-positive patients (120 U/ml) had higher IgG concentrations than culture-negative patients (64 U/ml). Using isolation of H. pylori or a positive biopsy urease test as a measure of true prevalence of infection, the sensitivity of serology was 96%, the specificity 42%, positive predictive value 67% and negative predictive value 90%. Seroprevalence increased with age, to a peak of more than 90% in blood donors aged 50-59 years and in patients aged over 60 years. The epidemiology of H. pylori in Barbados is similar to that in developed countries, where few children are infected, but resembles other developing countries in the high seroprevalence observed in middle-aged adults. Our results confirm the utility of serology for detecting H. pylori by a non-invasive technique.

Anterior horn cell degeneration has only occasionally been noted in patients with tropical spastic paraparesis associated with human T lymphotropic virus type-1 (HTLV-1) infection. We report on three adult patients with HTLV-1-associated polymyositis who had clinical evidence of anterior horn cell degeneration. One patient had moderate proximal weakness and muscle wasting in all four limbs, while two had mild upper limb weakness with more profound proximal weakness and wasting in the lower limbs. In all three patients, electromyographic findings were compatible with motor unit loss and muscle biopsies showed mononuclear inflammatory cell infiltration; muscle biopsies in two patients showed features of denervation. Immunoglobulin G (IgG) antibodies to HTLV-1 were detected by enzyme-linked immunosorbent assay (ELISA) and confirmed by Western immunoblot in serum and cerebrospinal fluid in all three patients. In two, cell cultures were established from peripheral blood lymphocytes and HTLV-1 antigen was identified by immunofluorescence and the ELISA antigen-capture technique using an anti-p19 HTLV-1 mouse monoclonal antibody. The three cases illustrate the variety of neuromuscular disease, other than spastic paraparesis, that may occur in HTLV-1 infection. In some cases of HTLV-1-associated polymyositis, anterior horn cell degeneration may make a significant contribution to the muscle atrophy observed.

We studied a 58-year-old black woman from Barbados who simultaneously developed myelopathy and lymphoma with human T-lymphotropic virus type I (HTLV-I) antibodies in serum and cerebrospinal fluid and died 3 years after onset. Neuropathological examination showed typical tropical spastic paraparesis (TSP). The polymerase chain reaction (PCR) demonstrated defective proviral genome retaining the HTLV-I pX and env regions in thoracic spinal cord, the level most severely affected. Defective HTLV-I in the nervous system retaining the pX region may be relevant to pathogenesis because circulating CD8+ cytotoxic lymphocytes specific for HTLV-I pX occur in HTLV-I myelopathy. This patient's lymph node biopsy specimen was consistent with Hodgkin's disease (HD), nodular sclerosis subtype, of B-cell origin. The PCR in the paraffin-embedded lymph node involved by HD failed to amplify HTLV-I proviral sequences. Complete HTLV-I proviral amplification was obtained in paraffin-embedded lymph nodes form positive controls (adult T-cell leukemia). To our knowledge the association of TSP and HD has not been reported previously. Despite claims that HD may be associated with HTLV-I, we demonstrated absence of HTLV-I-infected T cells in the lymphoid infiltrate of HD in this case, positive HTLV-I serology notwithstanding.

A case of fatal infection with Shigella flexneri is reported. The 19-year-old male patient who presented with fulminating haemorrhagic colitis died nine days after the onset of symptoms. The infecting strain of Shigella flexneri was resistant to multiple antimicrobial agents, including amoxycillin, co-trimoxazole and chloramphenicol.

A case of a 36-year-old woman with a past history of uterine leiomyosarcoma and an intracerebral metastasis is reported. The patient presented with a 24-hour history of severe headache with coma, and the CT findings were consistent with a metastatic lesion. Pathological examination of the operative specimen showed features of a leiomyosarcoma. Uterine leiomyosarcoma is an uncommon tumor and metastasis to the brain is rare.

A case is described of a 3-year-old boy with acute lymphoblastic leukaemia (ALL) who presented initially with aspergillosis of the nasopharynx. Fungal infection with Aspergillus species is not uncommon in immunosuppressed children, but this case is noteworth in that the disease presented at the onset of therapy rather than during the phase of treatment, with maximum immunosuppression following chemotherapy. This type of infection is usually associated with the treatment of acute non-lymphoblastic leukaemias (AML) rather than ALL, and prolonged periods of neutropenia which results from aggressive treatment. This patient responded rapidly to treatment with amphotericin B, coincident with resolution of his neutropenia as the underlying disease was treated, eventually eradicating the fungus.