Israel Medical Association Journal

Background: Two recent studies found that the prevalence of cryptosporidiosis among children in Israel was 3.4-7.4%.

Objectives: To assess the cumulative infection rate by testing immunoglobulin A and G seroprevalence for Cryptosporidium in children and adults in Israel.

Patients and Methods: The seroprevalence of IgA and IgG anti-Cryptosporidium antibodies was determined by an enzyme-linked immunosorbent assay procedure in a group of 163 healthy children and adults.

Results: The overall seroprevalence rates for IgG, IgA, both IgA and IgG, and any immunoglobulin were 12.6%, 23%, 30% and 65.6% respectively. Half the children under the age of 12 years were already infected, with seroprevalence increasing to 95.6% in those over age 13 (P<0.05). Seropositivity for IgG or IgA did not significantly increase with age.

Conclusions: These results indicate that a large percentage of healthy children and adults in northern Israel have been infected with Cryptosporidium, and at early ages.

Background: Exposure of newborn animals to high concentrations of oxygen leads to diffuse alveolar damage similar to that seen in bronchopulmonary dysplasia in human infants. Therefore, neonatal rats are a suitable practical model of hyperoxic lung damage in human infants.

Objective: To determine the involvement of tumor necrosis factor-alpha and interleukin-6 in lung injury in neonatal rats exposed to 100% O2 concentration.

Methods: A randomized controlled study was designed in which litters of term Sprague-Dawley rat pups were assigned to experimental or control groups. The pups in the experimental group were placed in 100% O2 from birth for 9 days, while the control pups were placed in room air. Twelve to 15 pups from each group were sacrificed on day 1, 3, 6, 9 and 13 after birth for bronchoalveolar lavage collection and lung histologic study. The bronchoalveolar lavage fluid was assayed for TNFα and IL-6.

Results: Newborn rats exposed to 100% O2 for the first 9 days of life showed severe pulmonary edema and hypercellularity on days 1 and 3, which then improved to nearly complete resolution on days 6 and 9. Pulmonary TNFα was produced early on O2 exposure (day 3) and pulmonary IL-6 later (days 6 and 9).

Conclusions: Hyperoxia induces sequential production of pulmonary TNFα and IL-6, which corresponds to the severity of the pathological findings and the known inflammatory and anti-inflammatory role of these cytokines.

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TNFα= tumor necrosis factor-alpha

IL-6= interleukin-6

Background: The arrival of 610,000 new immigrants to Israel from the former Soviet republics accounted for 58% of the population growth in the early 1990s.

Objective: To compare the coronary angiographic findings and risk factors between the new immigrants and local Jewish and Arab patients in this era of cost containment.

Methods and Results: A total of 550 consecutive patients - 314 Jews, 95 new immigrants and 141 Arabs - were catheterized and analyzed during a 5 month period in 1995. Of this group 403 were males (73%). The mean age was 63.6±10.2 years among new immigrants, 62.4±9.4 among Jews, and 55.1±10.9 among Arabs (P<0.05). Immigrants, including those under age 60, had the highest prevalence of multivessel disease (88.7%). Arabs had a high prevalence of single vessel disease (34.6%) and a low prevalence of multivessel (65.4%) and left main coronary disease (5.6%). Age, gender, risk factors and ethnic origin in descending order were determinants of the extent of coronary angiographic disease as revealed by multiple regression analysis.

Conclusion: New immigrants had the most extensive angiographic coronary involvement, while Arab patients were younger and had less severe coronary artery disease. More intensive risk factor modification may have a major impact on disease progression particularly in the new immigrant subgroup. 

Background: Cell-mediated immunity is impaired in uremia. Cell-matrix interactions of immune cells such as CD4+T lymphocytes with extracellular matrix are an important requirement for an intact immune response. The adherence of CD4+T cells of healthy subjects (normal T cells) to ECM components is inhibited in the presence of uremic serum. Such decreased adhesive capacity is also found in T cells of dialysis patients. Various chemokines and cytokines affect the attachment of CD4+T cells to ECM.

Objective: To evaluate chemokine (MIP-1β and RANTES) and tumor necrosis factor α-induced adhesion of CD4+T cells to ECM in a uremic milieu.

Methods: We examined adhesion of normal CD4+T cells (resting and activated) to intact ECM in response to soluble or bound chemokines (MIP-1β and RANTES) and to TNF-α following incubation in uremic versus normal serum. Thereafter, we evaluated the adhesion of resting CD4+T cells from dialysis patients in a similar fashion and compared it to that obtained from a healthy control group.

Results: Addition of uremic serum diminished soluble and anchored chemokine-induced attachment of normal resting and activated CD4+T cells to ECM compared to a normal milieu (a peak response of 10–11% vs. 24–29% for soluble chemokines, P<0.001; 12–13% vs. 37–39% for bound chemokines on resting cells, P<0.01; and 18–20% vs. 45–47% for bound chemokines on activated cells, P<0.02). The same pattern of response was noted following stimulation with immobilized TNF-α (7 vs. 12% for resting cells, P<0.05; 17 vs. 51% for activated cells, P<0.01).  Adherence of dialysis patients’ cells to ECM following stimulation with both bound chemokines was reduced compared to control T cells (15–17% vs. 25–32%, P<0.0000). In contrast, adherence following stimulation by TNF-α was of equal magnitude.

Conclusions: Abnormal adhesive capacity of T lymphocytes to ECM in uremia may, in part, be related to a diminished response to MIP-1β, RANTES and TNF-α. However, whereas reduced adhesion to chemokines was present in both normal CD4+T cells in a uremic environment and in dialysis patients’ T cells, TNF-α-induced adhesion was found to be inhibited only in normal cells in a uremic milieu.

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ECM = extracellular matrix

TNF-α = tumor necrosis factor-a

Background: Over a 12 month period, the Israel Transplant Center doubled the number of donors by assigning a nurse coordinator to each of 22 hospitals around the country and by using kidneys from elderly donors.

Objective: To evaluate the impact of our "marginal donors" policy on the results immediately following transplantation.

Methods: Between October 1997 and September 1998, 140 cadaveric kidney transplantations from 72 donors were performed in Israel. We defined two groups of recipients: patients with immediate graft function and patients with either delayed graft function requiring >1 week of dialysis post-transplant or with primary graft non-function. We compared the following parameters between groups: donor and recipient age and gender, cause of donor’s death, length of stay in the intensive care unit, vasopressor dosage and creatinine levels before harvesting, cold ischemic time, and the number of recipient grafts.

Results: There were 102 recipients (72.8%) with immediate graft function and 38 with either PNF (n=13, 9.3%) or DGF (n=25, 17.9%). On regression analysis, donor age >50 year and retransplantation were significant risk factors for PNF or DGF (odds ratio 4.4 and 2.8, respectively). Of the 56 kidneys from donors >50 years old, 21 (37.5%) developed either PNF (n=9) or DGF (n=12).

Conclusions: We conclude that kidneys from donors over age 50 are at increased risk for graft non-function or delayed function. Better assessment of functional capacity of kidneys from “aged” donors may help to choose appropriate donors from that pool.

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PNF = primary graft non-function

DGF = delayed graft function

Background: DHEAS, the most abundant steroid secreted by the adrenal cortex, is suggested to have an important role in the development of immune reaction by activating T cell function and increasing antibody response, and has been tried as a vaccine adjuvant in elderly people.

Objectives: We examined the correlation between endogenous DHEAS and antibody response in the neonatal period by comparing the serum DHEAS levels with the amount of antibody response against hepatitis B vaccination in neonates.

Methods: Vaccine was administered to 12 healthy infants within 24 hours of birth (day 0), and blood specimens were obtained on days 0 and 30 for determination of anti-hepatitis B surface antibody concentration and DHEAS levels.

Results: DHEAS levels varied widely (range 0.38-3.70 μg/ml, mean±SD 2.14±0.98). While we could identify two groups of patients - those with high DHEAS levels (2.90±0.56) and those with lower levels (1.30±0.56) - there was no correlation between DHEAS levels and the antibody response to hepatitis B vaccine (γ=-0.05).

Conclusions: In neonates, antibody response to hepatitis B vaccine does not correlate with DHEAS serum levels. These results do not support the usage of DHEAS as a vaccine adjuvant in neonates.

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DHEAS= dehydepiandrosterone sulphate

Background: The course and outcome of appendicitis in the elderly differs from that of the general population. The rates of perforated appendices, error in diagnosis, postoperative complications and mortality may be related to the time lapse between onset of symptoms and admission, and hence delay in surgery.

Objectives: To evaluate if these factors have improved in recent years.

Methods: A retrospective study was carried out of all 61 patients over age 60 who underwent appendectomies in a major metropolitan hospital during 1988-98.

Results: We found that most patients had appendectomies within the first 24 hours of admission and within 3 days of symptoms. Rate of perforation was 43%, error 5.6%, morbidity 41%, and mortality 3.2%.

Conclusions: The high rate of appendix perforation in the elderly is not due to delay. The literature reveals little improvement in the statistics of the disease over the last five decades, despite advances in imaging and surgical technique. This may be explained by the increasing inclusion of octogenarian patients.