294 Stem Cell Enriched Fat Grafts Versus Autologous Fat Grafts for Facial Reconstruction: A Systematic Review and Meta-Analysis

Aim

To compare the results of stem cell-enhanced fat grafting to autologous fat grafting for face reconstruction.

Method

A systematic review and meta-analysis were carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Guidelines, and an electronic search was carried out to identify all Randomised Controlled Trials (RCTs), case control studies, and cohort studies comparing the outcomes of stem cell-enrichment fat grafting versus routine fat grafting for facial reconstruction. The primary outcome measures were volume retention and infection rate. Secondary outcome measures included post-surgery patient satisfaction, redness and swelling, fat necrosis, cysts, and operation time. For the analysis, fixed and random effects modelling were utilised.

Results

Eight studies with a total of 275 participants were assessed. In terms of mean volume retention, there was a significant difference between the stem cell-enrichment fat grafting and routine grafting groups (standardised Mean Difference [MD] = 2.49, P 0.00001). However, there was no significant difference in infection rates between the two groups (OR = 0.36, P = 0.30). Except for the operation duration, which was shorter in the latter, the intervention group had similar results to the control group for all secondary outcomes.

Conclusions

When compared to conventional fat grafting, stem cell-enriched fat grafting is a better alternative for facial reconstruction surgery since it enhances mean volume retention and does not worsen patient satisfaction or surgical complications.

926 Peri-Operative Antibiotic Prophylaxis in K-Wire Fixation: Systematic Review and Meta-Analysis

Aim

There are presently no established standards on whether antibiotic prophylaxis is necessary during Kirschner wire (K-wire) fixation in order to reduce infection rates. The outcomes of antibiotic prophylaxis vs no antibiotic prophylaxis in K-wire fixation, were compared.

Method

A systematic review and meta-analysis were carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Guidelines, and an electronic search was carried out to identify all Randomised Controlled Trials (RCTs) and non-randomised studies comparing the outcomes of antibiotic prophylaxis groups versus those without antibiotic in patients undergoing K-wire fixation. The primary outcome was the rate of infection. The depth of infection was used as a supplementary outcome measure. The analysis employed fixed effects modelling.

Results

Four retrospective cohort studies and one randomised controlled trial with a total of 2316 patients were found. In terms of infection rate, there was no significant difference between the preventive antibiotic and no antibiotic groups (Odds Ratio [OR] = 0.72, P = 0.18). In terms of secondary outcomes, antibiotic prophylaxis had the same depth of infection rates as no antibiotics.

Conclusions

Giving antibiotics peri-operatively showed no significant difference in managing infection rates. However, more clinical trials are required to ascertain this evidence.

Application of a Graded Approach to Support the National Research Universal Reactor U-2 Experimental Loop Return to Service

The National Research Universal (NRU) reactor at Canadian Nuclear Laboratories (CNL) operated safely for over 60 years and supported a wide range of applications including, testing of fuels and materials under typical power reactor conditions in two experimental loops (U-1 and U-2). Both experimental loops had been taken out of service to address seismic deficiencies. CNL applied a graded approach to successfully return one of these loops, the U-2 Loop to service. The graded approach, without compromising safety, applied a risk informed methodology commensurate to the potential risk posed by the operation of the U-2 Loop. The work enabled the U-2 Loop to resume operation until the NRU reactor was permanently shut down in Mar. 31, 2018, generating valuable data that will be used in the development of advanced nuclear fuels and materials. This paper describes the graded approach employed by CNL that supported U-2 loop return to service (RTS). The use of graded approach is articulated to support development of safety and licensing cases for small modular reactor projects.

The immune microenvironment in cutaneous leishmaniasis

BACKGROUND

Cutaneous leishmaniasis is an infection that has spread to non-endemic regions, stimulating recent interest for the enhanced understanding of this disease. Downregulation of the CD1a receptor on Langerhans cells has been described in various cutaneous infections.

OBJECTIVE

In this study, the immune response across different Ridley patterns and parasitic indices is outlined in a case series of cutaneous leishmaniasis.

METHODS

Skin punch biopsies from the interface of normal and lesional cutaneous leishmaniasis were collected from 33 patients with molecularly confirmed Leishmania tropica or L. major infection. Ridley patterns (2-5) were assessed for various clinicopathological features including age, gender, disease duration, parasitic index and constituents of the inflammatory infiltrate. CD1a, CD68, CD3, CD4, CD8, CD20 and CD138 stains were performed on normal skin tissue, cutaneous leishmaniasis biopsies and cytospin/cell block cytology preparations of cultured leishmania promastigotes. CD1a was quantified per mm2 in the epidermis and dermis. The remaining stains were graded according to a 4-tiered grading system [0 (0-4%); 1 (5-24%); 2 (25-49%); 3 (50-74%) and 4 (75-100%).

RESULTS

Total CD1a expression significantly decreased (14-fold) from parasitic indices (0-2) to (5-6); (ρ < 0.001). CD1a expression in the epidermis was at least 5-fold lower than normal skin (58 vs. 400 cells/mm2), inversely correlating with the parasitic index. There was an increase in dermal CD1a Langerhans cells (33 vs. 0 cells/mm² in the dermis). CD1a and CD68 staining of amastigotes was strong and diffuse, whereas promastigotes were negative. The major inflammatory infiltrate, in all Ridley patterns, consisted of macrophages and double-negative CD3(+) CD4(-) CD8(-) T lymphocytes. The double-negative CD3 T cells formed a ring around the parasitic laden macrophages. Apart from CD1a, there was no significant difference in inflammatory markers between the various Ridley patterns and parasitic indices. Disease duration did not correlate with Ridley pattern.

CONCLUSION

The significant decrease in CD1a expression is postulated by two mechanisms; either via direct CD1a receptor uptake by leishmania amastigotes and/or negative feedback inhibition of CD1a Langerhans cells by double-negative CD3 T-regulatory cells. Modulation of the immune microenvironment in cutaneous leishmaniasis represents a potential therapeutic and prophylactic target.

Designing the Model Human Cochlea: An Ambient Crossmodal Audio-Tactile Display

We present a model human cochlea (MHC), a sensory substitution technique and system that translates auditory information into vibrotactile stimuli using an ambient, tactile display. The model is used in the current study to translate music into discrete vibration signals displayed along the back of the body using a chair form factor. Voice coils facilitate the direct translation of auditory information onto the multiple discrete vibrotactile channels, which increases the potential to identify sections of the music that would otherwise be masked by the combined signal. One of the central goals of this work has been to improve accessibility to the emotional information expressed in music for users who are deaf or hard of hearing. To this end, we present our prototype of the MHC, two models of sensory substitution to support the translation of existing and new music, and some of the design challenges encountered throughout the development process. Results of a series of experiments conducted to assess the effectiveness of the MHC are discussed, followed by an overview of future directions for this research.

Humoral immune responses in human onchocerciasis: detection of serum antibodies in early infections

Sera of children (aged 1-15 years) living in a hyperendemic onchocerciasis area (Mali) were tested for antibodies by an enzyme-linked immunosorbent assay (ELISA) and a radioallergosorbent test (RAST), with an extract of adult Onchocerca volvulus as antigen. Serological results were related to age (equivalent to time of residence in the endemic area) and to parasitological findings (detection of skin microfilariae). This longitudinal study (over three years) allowed us to follow early antibody responses in exposed children with no parasitological or clinical evidence of infection and in children who became microfilaria-positive. Serum antibodies against O. volvulus could be detected one to three years before skin microfilariae. RAST, which detected circulating immunoglobulin E (IgE) antibodies, was more sensitive than ELISA in prepatent infections and gave more positive results for exposed but parasitologically negative individuals than did ELISA. During patent infection, IgE antibody levels tended to decrease in about half those infected, whereas in most children non-IgE antibodies showed no significant changes.

Dracunculiasis eradication

Dracunculiasis is a disease caused by a parasite transmitted through infected drinking water. The International Drinking Water Supply and Sanitation Decade (1981-1990), provided a unique opportunity to eliminate the disease. The strategy of the eradication campaign was based on provision of safe drinking water supply, intensified case containment and health education. An appropriate epidemiological surveillance system was established to guide and evaluate the eradication effort. From an estimated 3.2 million people affected by the disease at the beginning of the campaign, the number of cases dropped to 10,674 by the end of year 2005. Currently the transmission of the disease takes place in 9 sub-Saharan countries only and another 7 countries are in the pre-certification stage. So far, 168 countries and territories have been certified free of transmission. However; eradication of the disease requires that all countries be certified free of transmission. With the support of the international community and the work of national dracunculiasis eradication programmes of affected countries, dracunculiasis may well be the first parasitic disease to be eradicated.

Phase II study of dexamethasone, ascorbic acid, thalidomide and arsenic trioxide (DATA) in high risk previously untreated (PU) and relapsed/refractory (RR) multiple myeloma (MM)

17535

Background: The combination of Thalidomide (T) and Dexamethasone (D) is often used first line in patients with MM. Arsenic trioxide (ATO) is active and well tolerated in patients with RR MM. ATO, D and T have non-overlapping toxicity. We therefore initiated a phase II study to assess the efficacy and toxicity of this combination in patients with high risk PU MM (serum B2 microglobulin>5.5, chromosome 13 or 14 abnormalities by FISH or the presence of peripheral plasma cells) and RR MM. Methods: On week 1, ATO was given at a dose of 0.25mg/kg IV on days 1–5. On weeks 2–12, ATO was given at the same dose twice weekly. On weeks 13–16, the patients did not receive treatment. Ascorbic acid 1000mg IV was given after each ATO infusion. D was given at a dose of 20mg orally on days 1–4 of a 28 days cycle, and T was started at a dose of 50mg daily and increased as tolerated to a dose of 100mg daily. A similar 16 weeks consolidation course was given. Maintenance included ATO 0.25mg/kg on days 1,8,15 and 22 every 12 weeks in addition to the above schedule for D, T and Ascorbic acid. Results: Sixteen patients were enrolled (3 with PU and 13 RR), 13 are evaluable for response. The median age was 57 years and 62% were males. The median number of prior chemotherapy regimen is 2 (range 0–6), 7 patients had received a prior T containing regimen, and 2 patients had received an ATO-containing regimen. Seven, seven and two patients had SWOG stages 2, 3 and 4 respectively. The mean serum B2 microglobulin was 7.1-mg/dL (s.d. 4.4). After a median follow up of 9.5 months (range 1–12), 9 patients progressed and 5 died. The median progression free survival was 9.4 months. The median progression free survival for responder has not been reached. Four patients had a PR (31%), 8 had stable disease (62%), and 1 had progressive disease. No patient had a QT>500 or a cardiac arrhythmia. Grade 3 leukopenia, anemia, neuropathy and renal failure occurred in 3, 2, 1 and 1 patients respectively. Three patients had a venous thromboembolic event (2 DVT and 1 PE). Conclusions: The addition of T to the combination of ATO, Ascorbic acid and D is safe, well tolerated and results in 30% PR and 61% stable disease in patients with poor risk MM.

[Table: see text]

Pott’s puffy tumour caused by mucormycosis

A case of Pott’s puffy tumour in a diabetic patient with renal failure is reported. The patient did not respond to intravenous antibiotics and further investigation revealed that the patient had mucormycosis. As far as we are aware, this is the first case of Pott’s puffy tumour due to mucormycosis to be reported in the literature.

Diuretic renogram clearance half-times in the diagnosis of obstructive uropathy: effect of age and previous surgery

Diuretic renography with radiotracers has been used successfully to diagnose obstruction in patients with hydronephrosis. Controversy persists with regard to the best approach for the interpretation of renogram curves: visual analysis or a quantitative index, i.e. the clearance half-time. The latter is often reported to be in the intermediate or non-diagnostic range. It is important to measure the incidence of equivocal half-times in various subsets of patients with hydronephrosis in order to determine in which settings the measurement of this index may be clinically useful. We performed a retrospective study of diuretic renograms performed at our institution between 1997 and 2000 for the evaluation of suspected uretero-pelvic junction (UPJ) obstruction. Vigorous intravenous hydration, exceeding current guidelines, was employed in these patients. Three hundred and seventy-seven renogram curves in 205 patients were analysed. Patients were divided into three groups: >1 year of age; <or=1 year of age; and those who had previously undergone surgical correction of obstruction regardless of age. Patients with reflux or anatomical abnormalities of the urinary tract, those with chronic renal failure, those with bilateral normal clearances before furosemide administration and those with unilateral normal clearances before furosemide administration with contralateral poor renal function were excluded. In the remaining 119 patients, 205 clearance half-times were classified as normal before furosemide, normal after furosemide (half-time, <10 min), prolonged (half-time, >20 min) or intermediate (half-time, 10-20 min). In patients >1 year of age, 37% of 101 renograms showed normal half-times before furosemide, 20% showed normal half-times after furosemide, 44% showed prolonged half-times and none (0%) showed an intermediate half-time. In patients </=1 year of age, there was a statistically significantly different distribution, with 48% of 64 renograms showing normal washout before furosemide, 16% showing normal clearance after furosemide, 19% showing abnormal half-times and 17% showing intermediate half-times. In 33 renograms from patients who had undergone corrective surgery, 49% had normal half-times, 24% had prolonged half-times and 27% had intermediate half-times. It can be concluded that, when using the selection criteria, hydration, acquisition and processing protocols and half-time definition employed in this study, the addition of a clearance measurement in patients older than 1 year with suspected UPJ disease enhances patient classification and may improve the diagnostic confidence. There was a significantly higher incidence of intermediate half-times in patients with native disease aged <1 year than in those >1 year. Caution is advised when interpreting this finding in this age group. The measurement of washout was less useful in patients who had undergone a corrective procedure, because of the high rate of 'indeterminate' and 'abnormal' values in spite of successful surgery. Vigorous intravenous hydration, exceeding current standards, may have contributed to the lower incidence of intermediate half-times than reported previously.

Influence of diagnostic and therapeutic doses on thyroid remnant ablation rates

Radioiodine ablation of thyroid tissue after subtotal thyroidectomy has been shown to decrease recurrence in certain subsets of patients with well-differentiated thyroid cancer. In a substantial percentage of cases (20-30%), initial ablation of the thyroid remnant fails, necessitating a second treatment. The factors associated with ablation failure are not fully understood. In particular, it is not certain whether the use of doses higher than 3.70 GBq would result in any additional benefit, or whether there is a 'stunning' effect of the diagnostic dose of 131I on the subsequent ablation rate. A retrospective analysis was performed of all patients (n=389) with well-differentiated thyroid cancer treated at our institution between 1992 and 2001. Remnant ablation success was determined by a whole-body radioiodine scan. The following factors, thought to be associated with thyroid remnant ablation, were studied by logistic regression analysis: age, gender, tumour histology, stage, pre-therapy neck uptake of 131I, diagnostic dose, ablation dose, time between diagnostic and therapeutic dose (T1), time between therapeutic administration and the first follow-up whole-body scan (T2) and the thyroid-stimulating hormone (TSH) level measured at the time of therapy. Follow-up whole-body scans were available in 214 patients. We found no association with age, gender, histology, TSH level, neck uptake, diagnostic dose and successful ablation. The therapeutic dose was the only variable found to be associated with success (odds ratio, 1.96 per 1.85 GBq increment; 95% confidence interval, 1.11-3.46). Our results confirm the presence of a significant percentage of ablation failures (24.4%) despite the use of high ablative doses (3.70-7.40 GBq). Higher therapeutic doses are associated with higher rates of successful ablation, even when administered to patients with more advanced stages. Using our protocol, higher diagnostic doses were not associated with higher rates of ablation failure.

Autonomous thyroid nodules visualized by positron emission tomography with 18F-fluorodeoxyglucose: a case report and review of the literature

A 41-year-old white female underwent a positron emission tomography with (18)F-fluorodeoxyglucose (FDG-PET) scan as part of staging follow-up for breast cancer. Focal FDG uptake was noted in the right neck. Further evaluation revealed only thyroid nodules and subclinical hyperthyroidism. A sodium pertechnetate thyroid scan showed two "hot" nodules in the right thyroid lobe corresponding to the focal uptake visualized on FDG-PET scan. Technetium-99m uptake was suppressed in the remaining thyroid gland. The patient underwent a subtotal thyroidectomy. Histopathologic evaluation revealed two hyperplastic nodules in each thyroid lobe. We review the literature with regard to FDG-PET imaging of normal and diseased thyroid tissue.

[The control of lymphatic filariasis]

Recent advances in the diagnosis, treatment, and pathophysiology of lymphatic filariasis have raised hopes for eradication. Development of an easy-to-use, rapid-format diagnostic tool has facilitated precise location of infectious zones thus allowing quick intervention. Two new drugs, i.e., ivermectin and albendazole, have been shown to be highly effective in the management of microfilariasis due to Wuchereria bancrofti, Brugia malayi, and Brugia timori thus greatly expanding a therapeutic arsenal once limited to diethylcarbamazine. The current eradication strategy is designed to break the chain of transmission in populations exposed to the risk of infection by administering a single dose of two drugs yearly for five to six years. Combined treatment using albendazole plus ivermectin or albendazole plus diethylcarbamazine has resulted in near-zero microfilaremia levels for at least one year. Based on these new developments, the World Health Assembly adopted a resolution calling on member states to work for the elimination of lymphatic filariasis as a public health problem. Thanks to the donation of albendazole and ivermectin by SmithKline Beecham and Merck & Co. respectively, the WHO has started a worldwide program and set up task force including a wide-range of actors in different fields for eradication of this disease affecting 120 million people.

Extra-pulmonary tuberculosis in patients with fever of unknown origin: clinical features and diagnosis

One hundred twenty-nine patients with extra-pulmonary tuberculosis admitted at the Abbassia Fever Hospital, NAMRU-3 during a seven year period (1991 to 1997) are described. Tuberculous peritonitis was diagnosed in 35 patients, tuberculous lymphadenitis in 32, intestinal tuberculosis in 19, genito-urinary tuberculosis in 14, skeletal tuberculosis in 13, disseminated miliary tuberculosis in 11, and splenic tuberculosis in 5 patients. The clinical picture included fever, and weight loss accompanied by anaemia and an elevated erythrocyte sedimentation rate in all patients.

Intestinal tuberculosis in patients with fever of unknown origin in Egypt

Nineteen patients with intestinal tuberculosis were admitted to the Abbassia Fever Hospital in the period 1991-1997. Fever, abdominal pain, diarrhea, and weight loss were the most common symptoms. Small bowel radiology and colonoscopy were helpful in establishing the diagnosis. The difficulties in diagnosing tuberculous enteritis and the need to consider seriously the possibility of this disease in such patients is most important and is discussed.

Temporal bone fracture following blunt trauma caused by a flying fish

Blunt trauma to the temporal region can cause fracture of the skull base, loss of hearing, vestibular symptoms and otorrhoea. The most common causes of blunt trauma to the ear and surrounding area are motor vehicle accidents, violent encounters, and sports-related accidents. We present an obscure case of a man who was struck in the ear by a flying fish while wading in the sea with resulting temporal bone fracture, sudden deafness, vertigo, cerebrospinal fluid otorrhoea, and pneumocephalus.

Lack of efficacy of low dose oral interferon alfa in symptomatic HIV-1 infection: a randomised, double blind, placebo controlled trial

BACKGROUND

Interferon alfa (IFN-alpha) exhibits dose related in vitro activity against human immunodeficiency virus (HIV), with complete inhibition of HIV replication at IFN-alpha concentrations > or = 256 IU/ml. In mid-1990, Kenyan investigators reported that oral administration of an extremely low dose (150 IU/day) of natural human (nHu) IFN-alpha resulted in complete alleviation of AIDS related complex and AIDS symptoms and resolution of opportunistic infections without additional treatment. Moreover, loss of HIV antibody seropositivity was reported in approximately 10% of treated patients. Subsequent small studies failed to substantiate these spectacular claims, but controversy on the efficacy of this treatment persisted.

METHODS

We studied 559 adult Ugandan patients with WHO stage 2-4 HIV infection and a Karnofsky performance score of more than 50, who had not received any drugs with antiretroviral activity in the previous 3 months. The patients were randomly assigned in a double blind fashion either to 150 IU oral nHuIFN-alpha/day or placebo. The duration of treatment was extended from 28 weeks to 60 weeks 9 months after enrollment had started. At that time 112 subjects had already received 28 weeks of treatment and been discontinued from the study.

RESULTS

Both study groups were comparable with respect to all baseline characteristics studied, except that the nHuIFN-alpha group had slightly lower absolute CD4+ lymphocyte counts (median 60.7 x 10(6)/l) than the placebo group (median 85.3 x 10(6)/l) (p = 0.033). Therefore, all analyses were adjusted for CD4+ lymphocyte counts at entry. In both treatment groups there was relentless progression of HIV disease. Subjects treated with nHuIFN-alpha and placebo had similar mortality, disease progression rates, decline of CD4+ lymphocyte counts and Karnofsky performance scores, and prevalence of symptoms. No patient reverted to HIV-1 seronegative antibody status. Serious adverse events were not seen. Quality control of the study medication documented that the active drug indeed contained IFN-alpha activity.

CONCLUSIONS

The current large, randomised, double blind, placebo controlled study did not show any benefit from oral treatment with 150 IU nHuIFN-alpha/day in a population of African patients with symptomatic HIV infection.

Safety evaluation of nonoxynol-9 gel in women at low risk of HIV infection

OBJECTIVE

To determine the safety of a vaginal microbicide, COL-1492, containing 52.5 mg nonoxynol-9, applied once daily for 14 days among healthy volunteers.

METHODS

A randomized, double-blind controlled trial with three arms, COL-1492 gel versus placebo gel versus no-treatment controls, was conducted. Outcomes of interest were reported genital symptoms, incidence of gynaecological signs, and incidence of genital lesions revealed by colposcopy. Participants were enrolled in four centres (Belgium, The Netherlands, and two in Thailand).

RESULTS

A total of 534 women participated in the study: 179 used COL-1492, 178 used placebo, and 177 were no-treatment controls. Study visits were scheduled 1 week prior to enrollment (day -7), day 0 (enrollment), day 8 and day 14. The most frequently reported genital symptom was vaginal discharge in both the COL-1492 and placebo groups. This appeared to be related to leakage of the product out of the vagina. The incidence of lesions associated with epithelial disruption (ulcers and abrasions) was very low (< 2%) and there was no statistically significant difference between the three groups. Of the lesions observed by colposcopy that did not involve epithelial disruption, petechial haemorrhage was the most frequently detected, with an incidence of 20.1, 9.0 and 7.3% in the COL-1492, placebo and control groups, respectively. COL-1492 users had a higher incidence of erythema (8.4 versus 2% in the other groups).

CONCLUSION

COL-1492 showed minimal toxicity when applied once daily. A Phase III trial to assess the product's effectiveness in HIV prevention is currently ongoing.

Splenic tuberculosis in patients with fever of unknown origin

Splenic tuberculosis is uncommon. We report here splenic tuberculosis in 5 patients with fever of over 3 weeks duration. In the 5 patients, abdominal ultrasonography and/or abdominal computed tomography revealed multiple hypoechoic and hypodense splenic lesions. Diagnosis required biopsy of cervical lymph nodes in four cases and splenectomy in one. Despite vigorous antituberculous therapy with isoniazid, rifampin, and ethambutol, the clinical condition of 2 of these patients worsened and splenectomy was done. Histological examination of a tissue specimen of the spleen showed multiple caseating granulomas.

Strategies and tools for the control/elimination of lymphatic filariasis

Lymphatic filariasis infects 120 million people in 73 countries worldwide and continues to be a worsening problem, especially in Africa and the Indian subcontinent. Elephantiasis, lymphoedema, and genital pathology afflict 44 million men, women and children; another 76 million have parasites in their blood and hidden internal damage to their lymphatic and renal systems. In the past, tools and strategies for the control of the condition were inadequate, but over the last 10 years dramatic research advances have led to new understanding about the severity and impact of the disease, new diagnostic and monitoring tools, and, most importantly, new treatment tools and control strategies. The new strategy aims both at transmission control through community-wide (mass) treatment programmes and at disease control through individual patient management. Annual single-dose co-administration of two drugs (ivermectin + diethylcarbamazine (DEC) or albendazole) reduces blood microfilariae by 99% for a full year; even a single dose of one drug (ivermectin or DEC) administered annually can result in 90% reductions; field studies confirm that such reduction of microfilarial loads and prevalence can interrupt transmission. New approaches to disease control, based on preventing bacterial superinfection, can now halt or even reverse the lymphoedema and elephantiasis sequelae of filarial infection. Recognizing these remarkable technical advances, the successes of recent control programmes, and the biological factors favouring elimination of this infection, the Fiftieth World Health Assembly recently called on WHO and its Member States to establish as a priority the global elimination of lymphatic filariasis as a public health problem.

Focal lesions of the spleen in patients with fever of unknown origin: sonographic patterns and diagnosis

A review of ultrasonic scans performed for 811 patients admitted at the Abbassia Fever Hospital between 1990 through 1996 for investigation of fever undiagnosed for over 3 weeks revealed 28 cases of focal splenic lesions. They included lymphoma in sixteen cases, tuberculosis in six cases, echinococcal cysts in three, abscess in two, and infarction in one. Final diagnosis was obtained by correlating the ultrasonography and clinical findings, together with pathologic, bacteriologic, serologic and angiographic data.

Frequent use of menfegol spermicidal vaginal foaming tablets associated with a high incidence of genital lesions

Menfegol is a spermicide with in vitro activity against human immunodeficiency virus (HIV). A randomized placebo-controlled safety study covered the use of menfegol foaming tablets for 14 days at increasing frequencies of insertion by 125 prostitutes in Dakar, Senegal. The frequencies of colposcopically diagnosed genital lesions were 5.0%, 11.8%, 27.8%, 49.7%, and 29.4% among menfegol recipients when tablets were used once every other day or 1, 2, 4, or 8 times a day, respectively (P < .05). Among placebo recipients, frequencies were 11.1% and 23.5% when tablets were used < 8 times daily and 8 times daily, respectively. There was no association between subjective genital symptoms and the incidence of colposcopically detected lesions. The high incidence of genital lesions when menfegol foaming tablets were used more than once daily suggests that their frequent use should not be recommended to prevent HIV transmission. In use at low frequency, the tablets' toxicity might be balanced by anti-HIV properties. Safety studies on vaginal microbicides should use objective methods, such as colposcopy, to assess the incidence of lesions.

The effects of vector control on the antibody response to antigens of Onchocerca volvulus

The effects of exposure to infective larvae on the antibody response to a cocktail of specific recombinant antigens of Onchocerca volvulus and to a worm extract were evaluated by comparing the responses of individuals from a vector controlled area with those from an area of continuing transmission by ELISA. Individuals from the vector controlled areas were found to have reduced responses to both antigen preparations. A microfilerdermic (mf-) individuals from the area of vector control exhibited significantly lower total and subclass IgG responses to the worm extract. In contrast, the responses to the cocktail of specific recombinants were significantly reduced in individuals from the area of vector control who were still microfilerdermia positive (mf+). The distribution of IgG subclass specific responses was similar to both antigen preparations, both dominated by the IgG4 and IgG1 subclasses. IgG1 responses to the worm extract remained elevated in the vector controlled individuals but IgG4 was significantly reduced in the mf- individuals. Both subclasses reflected the total IgG response to the cocktail of recombinants and were significantly reduced in individuals from the vector controlled area, when compared to individuals from the hyperendemic area. IgG1 responses to the cocktail of recombinants are significantly lower than IgG4 in all individuals and virtually absent in individuals from the vector-controlled area. Measuring total IgG and IgG4 is more sensitive than IgG1 in detecting infection, 100 or 97% respectively, but they remain elevated in the individuals from the vector controlled areas even after 8-10 years interruption of transmission. These results have important implications for the serological monitoring of control programmes in individuals who have previously been infected.

An immunogenic Onchocerca volvulus antigen: a specific and early marker of infection

Onchocerciasis (river blindness) is a serious health problem and a severe obstacle to social and economic development, especially in Africa. A complementary DNA fragment coding for an Onchocerca volvulus antigen (OV-16) was cloned and expressed in the plasmid vector pCG808fx. Immune responses to this O. volvulus-specific recombinant antigen were detectable in patients with documented onchocerciasis; the antibody response was also detectable at 3 months and at more than 1 year before infection could otherwise be detected in humans and in chimpanzees experimentally infected with O. volvulus third-stage larvae.

Identification of an Onchocerca volvulus cDNA encoding a low-molecular-weight antigen uniquely recognized by onchocerciasis patient sera

The primary structure of an immunodominant antigen of the filarial parasite, Onchocerca volvulus was deduced from cDNA sequence analysis. Using affinity-purified antibody from onchocerciasis patients from West Africa, we have isolated a cDNA clone from a lambda gt11 cDNA expression library derived from microfilariae-producing female O. volvulus. The open reading frame encodes 152 amino acids, and the deduced sequence predicts a Mr of 16,850 (consistent with the apparent Mr of 18,000 of the immunoprecipitated in vitro translated product). The primary translation product contains a putative signal peptide of 16 amino acids. The mRNA coding for this antigen has an estimated size of 950 nucleotides. Furthermore, immunoelectron microscopy established that the antigen encoded by this clone is present in the hypodermis, the cuticle, and in the uterus of the filarial worms. Since this antigen is recognized exclusively by sera from onchocerciasis patients, and not by other sera from patients infected by other filarial parasites, it may prove to be an especially valuable tool for improving the specific diagnosis of onchocerciasis.

A community trial of ivermectin in the onchocerciasis focus of Asubende, Ghana. II. Adverse reactions

A community trial of the microfilaricide ivermectin undertaken in an hyperendemic focus of blinding onchocerciasis in Ghana. One objective was to investigate the safety of this new drug when used in mass treatments. 14,911 persons (61.5% of the census population) were treated with ivermectin. Of these, 15% reported with adverse reactions which were generally similar to those reported in the clinical trials. However, cutaneous reactions were relatively less frequent while brawny oedema of the limbs and inguinal gland pain were important. The severe reactions consisted of 37 cases of Severe Symptomatic Postural Hypotension (SSPH), 13 cases of severe fever and two cases of severe dyspnoea. The latter two cases represented life threatening situations, but there was no evidence that they were complications of ivermectin treatment. Only four of the SSPH cases required treatment. All severe adverse reactions were managed successfully and recovered within one day, usually within a few hours. The incidence of adverse reactions was highest the first day after treatment. Thirteen cases of delayed reactions were reported during a four-week follow-up. There was a highly significant relationship between incidence of adverse reactions and intensity of infection but no relation with ivermectin dosage within the range of 130-200 mcg/kg. The results suggest that ivermectin is sufficiently safe to be used in mass treatments. However, mass distribution of this drug should not be undertaken without adequate monitoring.

Cloning and characterization of an Onchocerca volvulus specific DNA sequence

A cloned sequence, pOvs134, was isolated from a genomic library prepared from Onchocerca volvulus of savanna origin in the plasmid pUC9. pOvs134 hybridizes to all the geographic isolates of O. volvulus tested from both the New and the Old World, but not to the species Onchocerca gibsoni, Onchocerca gutturosa, Onchocerca ochengi, Onchocerca cervicalis, the filarial parasites Brugia malayi, or Dirofilaria immitis, nor to human or simuliid DNA. As little as 250 pg of DNA can be detected on a dot blot hybridization, suggesting that pOvs134 is sensitive enough to detect a single third stage larva. DNA sequence analysis of the inserted DNA of pOvs134 revealed that it consisted of twelve examples of a 149-bp repeat. The sequence of this repeat is strikingly similar to that of two O. volvulus genomic clones previously described, one of which has been reported to be specific for forest form O. volvulus, and one of which hybridizes to genomic DNA of several species of Onchocerca. These results suggest that the 149-bp repeat sequence is highly repeated in the genome of O. volvulus, and that variants of this repeat with different specificities exist.

Evaluation of a specific enzyme immunoassay for onchocerciasis using a low molecular weight antigen fraction of Onchocerca volvulus

A micro-ELISA technique has been developed for the diagnosis of onchocerciasis. With the use of a low molecular weight (LMW) fraction of a soluble, adult Onchocerca volvulus extract as an antigen, the problem of nonspecificity observed with the crude worm extract is negligible. Seventy-three sera from proven cases of other filarial infections were weakly reactive or nonreactive. From cross-sectional and longitudinal surveys in a West African village hyperendemic for onchocerciasis, we concluded that this assay detects antibodies elicited when female worms start to produce microfilariae. Thirty-two of 33 children aged less than or equal to 15 years with positive skin snips were seropositive. High antibody levels could also be found in children who only became parasitologically positive 1-4 years after seroconversion. This leads to the conclusion that serology is more sensitive than the 2-snip method. In individuals with chronic infection (exposed for greater than 15 years), antibody titers were consistently lower (independent of the density of skin microfilariae) than in the early phase of a patent infection. A comparative serological study in a mesoendemic village revealed that the assay can serve to assess onchocerciasis prevalence by testing individuals aged 5-15 years.

Adverse reactions after large-scale treatment of onchocerciasis with ivermectin: combined results from eight community trials

Eight community trials were carried out by the Onchocerciasis Control Programme in West Africa to determine the safety of the new microfilaricide ivermectin during large-scale treatment of onchocerciasis. The trial areas were located in eight different countries and varied greatly in endemicity level; a total of 50,929 persons were treated and monitored for 72 hours. Overall treatment coverage was 60% of the census population, the main reasons for non-treatment being the exclusion criteria. Of those treated, 9% reported with adverse reactions, 2.4% with moderate reactions, and 0.24% with severe reactions. Most reactions were reported during the first day of follow-up, the most frequent severe reaction being severe symptomatic postural hypotension (in 49 cases). Three cases of severe dyspnoea were life-threatening but their relationship with ivermectin treatment is uncertain. The incidence of adverse reactions was directly related to skin microfilarial load and was highest in the foci with the highest endemicity levels. Treatment resulted in 98% reductions in mean microfilarial loads at all endemicity levels. The benefit of treatment largely compensated for the discomfort due to adverse reactions, which were all transient and managed successfully. Ivermectin thus appears to be sufficiently safe for large-scale treatment but monitoring by resident nurses for at least 36 hours is recommended.

Construction of Onchocerca volvulus cDNA libraries and partial characterization of the cDNA for a major antigen

Adult Onchocerca volvulus were isolated from nodules removed from onchocerciasis patients at four locations--two in the West African Sudan-savanna region (near Bamako, Mali, and Touboro, Cameroon), one in a West African forest region (Kumba, Cameroon) and one near Guatemala City, Guatemala. Four different cDNA expression libraries were constructed in bacteriophage lambda gt11 using poly(A)+ RNA from the adult female worms. Individual cDNA clones of single copy genes were used to compare the genomes of parasites from the different locales and to show that the haploid genome of O. volvulus is 1.5 x 10(8) base pairs. About 1 in 700 recombinant clones in each of the four amplified cDNA libraries produces a fusion protein recognized by pooled human anti-O. volvulus antisera. Partial sequence determination of a 2.0 kb cDNA clone for an O. volvulus protein that induces an immunodominant response in rabbits revealed that this antigen has sequence similarities with Caenorhabditis elegans myosin and with schistosome paramyosin (which confers partial protection against schistosome infection). The four cDNA libraries have been deposited with American Type Culture Collection (ATCC), 12301 Parklawn Drive, Rockville, MD 20852, U.S.A., for general distribution under ATCC Number 37509.

Population dynamics of Onchocerca volvulus after 7 to 8 years of vector control in West Africa

In an attempt to describe the changing population dynamics of Onchocerca volvulus during a period of vector control, nodulectomies were undertaken in 256 patients from ten villages in the Onchocerciasis Control Programme (OCP) and in 74 patients from two villages in an area with ongoing transmission. A total of 1198 nodules were excised and 4350 adult worms were isolated and examined for viability and productivity. In the OCP villages, the worm population is ageing and dying without replacement by new generations of parasites and various findings signal a breakdown of the worm population after about 12 years interruption of transmission. The sexual activity of the worms was significantly reduced. A Productivity Index was developed to measure the microfilariae production at the nodule level. The reduction in this index for the OCP villages correlates closely with the decline over the control period in the community microfilarial loads in the skin. The results show that it is not only the longevity of the parasite which will determine the duration of vector control, but that the reduced productivity of the ageing parasite population is of equal importance.

Characterization of an Onchocerca-specific DNA clone from Onchocerca volvulus

A genomic library of a savanna isolate of Onchocerca volvulus was screened to detect recombinant plasmids containing highly repeated DNA sequences of this parasite. Four recombinant plasmids were identified which hybridized specifically to Onchocerca DNA, but not to DNA from humans, black flies, Brugia malayi, B. pahangi, or Wuchereria bancrofti. The recombinant plasmids had a low level of homology to Dirofilaria immitis. All recombinant plasmids contain related DNA sequences based on Southern hybridization analysis. Sequences related to these recombinant plasmids are present in different geographic isolates of O. volvulus and O. ochengi, an animal parasite. Two of the recombinant plasmids contain sequences also found in O. lienalis. One recombinant plasmid, puOvs3, has been characterized in detail, including DNA sequence determination. Radiolabeled puOvs3 is able to detect 100 pg of genomic DNA isolated from O. volvulus worms from both savanna and forest regions. It can differentiate O. volvulus from O. ochengi by Southern blot analysis.

A DNA sequence specific for forest form Onchocerca volvulus

Onchocerciasis, or river blindness, is caused by infection with Onchocerca volvulus, a filarial parasite which infects about 40 million people in Africa and Latin America. Epidemiological, clinical, entomological and serological studies of African onchocerciasis led to the hypothesis that Onchocerca volvulus exists in different forms in the forest and savannah. It is uncertain if these differences are due to genetic differences within O. volvulus itself, or to epigenetic factors, such as differences in the host populations. To date no basic biochemical differences between the forest and savannah populations of O. volvulus has been found, although isoenzyme studies have shown that differences in allele frequency between forest and savannah populations exist. Here we describe the isolation of a DNA sequence that seems to be specific for the forest form of O. volvulus, the first indication of a basic genetic difference between the savannah and forest forms.

[Role of children in the evaluation of the Onchocerciasis Control Program in West Africa]

Incidence of onchocercal infections is studied in children borne since the start of the larvicidal treatments of the Onchocerciasis Control Programme in West Africa (OCP). A total of 8088 children, originating from 155 villages widely distributed throughout the initial area of the OCP were examined for microfilariae of O. volvulus. 37 were found infected. If there had not been control measures, 652 children would normally have become infected in such a sample. It is considered that in the centre of the OCP area which constitutes approximately 90% of the total, transmission has been interrupted (1 child infected among 5,886 examined in the centre). The remaining 36 cases are spread over two quite distinct marginal zones of the OCP where transmission persisted because of reinvasion by blackflies coming from untreated areas, or because of insecticide vector resistance, or because of occasional treatment failures. The entomological indices confirm perfectly the epidemiological findings in the central region as well as in the marginal zones.

Immediate effect of expiratory loading on left ventricular stroke volume

While the steady-state effects of positive pleural pressure on the circulation have been extensively studied, less is known about the immediate effects of positive intrathoracic pressure on cardiac dynamics. Therefore, we performed electrocardiographically gated radionuclide ventriculography with a respiratory gating technique in nine healthy subjects during quiet breathing and during expiration against a 24 cm H2O expiratory threshold load. During expiration, respiratory loading caused an increase in stroke counts by 29.4% (p less than .001) due to an increase in end-diastolic counts of 26.1% (p less than .001). End-systolic counts also rose 18.8% (p less than .05). The ejection fraction did not change significantly. These findings indicate that the increase in left ventricular stroke volume that occurs during the first 1 or 2 beats of a loaded expiration is due to an increase in left ventricular filling and not to augmentation of left ventricular ejection. This immediate increase in pulmonary venous return may reflect increased distensibility of the left ventricle due to decreased filling of the right ventricle.

Cloning and characterization of two Onchocerca volvulus repeated DNA sequences

Two repeated sequences, plasmids pOV8 and pOV26, were cloned and characterized from the filarial parasite Onchocerca volvulus. Both clones can be used to distinguish O. volvulus DNA from other Onchocerca species or other nematodes by restriction fragment length polymorphisms, but neither clone can differentiate between DNA from savanna (Mali) or forest (Ivory Coast) O. volvulus isolates. DNA from one O. volvulus infective larva can be detected by both clones in dot blot hybridization assays. Neither clone cross hybridizes with DNA from host or vector species (human or simuliid, respectively). pOV26 is a member of an interspersed repeated DNA family composed of at least 100 members, and is only observed in the genus Onchocerca. Repeated DNA clone pOV8 cross reacts with DNA from other parasitic filarial nematodes, and is also present in at least 100 copies per O. volvulus genome. pOV26 is a potential tool in the diagnosis of human onchocerciasis, since it is specific for the genus Onchocerca. In the future, we plan to look for regions of these repeated sequences which may serve as a basis for the development of probes to discriminate among Onchocerca species and strains using a simple dot hybridization test.

A force-of-infection model for onchocerciasis and its applications in the epidemiological evaluation of the Onchocerciasis Control Programme in the Volta River basin area

A simple force-of-infection model for onchocerciasis has been developed for a study of the age-specific epidemiological trends during a period of vector control in the Onchocerciasis Control Programme in the Volta River basin area (OCP). The most important factors included in the model are the longevity of an infection, the aspect of super-infection, age-specific exposure, and the intensity of transmission during the pre-control period. The aim of the study was to determine the most appropriate statistics for the epidemiological evaluation in the OCP. There was generally good agreement between the epidemiological trends, predicted by the model, and the observed trends in the prevalence and mean load of microfilariae in skin snips taken from a cohort population from 23 villages in an area with 8 years of successful vector control in the OCP. It is concluded that the epidemiological trends during the control period are not uniform but depend on the initial age and the initial endemicity level of the population. The epidemiological indices for cohorts of children, born before the start of control, will not show a decrease during the first 8 years of interruption of transmission. The prevalence is too insensitive to be useful for the evaluation in hyperendemic villages during most of the control period. The most sensitive and meaningful statistic for a comparative analysis and for the assessment of epidemiological changes is the geometric mean microfilarial load in a cohort of adults. This index, which is called the Community Microfilarial Load (CMFL), is now routinely used in the OCP. The new analytical methodology has enabled a much better appreciation of the significant epidemiological impact of 8 years of vector control in the OCP. Several related aspects of the pre- and post-control dynamics of onchocerciasis infection are also discussed and priorities are formulated for further work on applied modelling of onchocerciasis.

Onchocerca volvulus: enzyme polymorphism in relation to the differentiation of forest and savannah strains of this parasite

Isozyme analysis was carried out on Onchocerca volvulus worms collected from Liberia, Ivory Coast, Burkina Faso and Sudan to see whether this technique could detect differences between forest and savannah populations of this parasite. A total of 243 forest and 189 savannah individual female worms were electrophoresed and stained for seven enzymes. Four showed some polymorphism, LDH, MDH, PGM and MPI and the other three, GAPDH, PEP and GPI were invariant. Statistical analysis of the results showed that the relative proportions of genotypes from within the different countries conformed to Hardy-Weinberg expectations. Pairwise comparisons of allele frequencies between countries showed that populations from Liberia and Ivory Coast had a very similar composition; there was some divergence between all the other pairs of populations and the genetic distance was calculated to summarize the degree of divergence. The number of loci examined was small and the genetic distances were within the range expected for separate geographical populations of the same species. The usefulness of this technique in worm identification is discussed.

Suramin in the treatment of onchocerciasis: the efficacy of low doses on the parasite in an area with vector control

In a village hyperendemic for onchocerciasis in Burkina Faso, where the vector had been controlled by the Onchocerciasis Control Programme since 1976, 65 patients were treated with doses of 37 to 71 mg/kg suramin in 1979. The viability and fertility of the adult parasites were studied in 217 nodules excised from 42 patients one month to four years after treatment using the collagenase technique. Most of the worms had survived the treatment. Male worms were more susceptible to suramin than female worms. The development of intrauterine stages initially continued, but was completely suppressed after several months. The female worms remained sterile in those patients who had received more than 60 mg/kg suramin. In other ones 11 and 13% of the female worms showed new embryonic stages in the uteri during two follow-up examinations in the second year. In a final examination in 1983 the reproduction had declined again. However, the reproductivity of the superannuated worms had considerably decreased in the untreated patients as well. All patients had shown a very high microfilardermia in 1979. After treatment the microfilarial densities dropped to levels near zero depending on the dose of suramin administered, but in none of the patients was the reduction complete during the first year of the treatment. Microfilariae gradually reappeared in the second year in several patients who had received less than 60 mg/kg suramin. In the final follow-up in 1983 most of the treated patients had become negative in skin counts, although they still harboured viable worms.(ABSTRACT TRUNCATED AT 250 WORDS)

Preliminary data on the genetic differentiation of Onchocerca volvulus in Africa (Nematoda: Filarioidea)

Data are reported on the genetic structure of three Onchocerca volvulus populations, respectively from Mali (savanna), Ivory Coast (forest), and Zaire (forest gallery in savanna). Electrophoretic analysis, carried out on 25 gene-enzyme systems, has shown a remarkable genetic heterogeneity existing within O.volvulus. Zaire and West Africa populations appear chiefly differentiated at Mdh-1 and 6Pgdh loci, their average Nei's genetic distance being 0.11. In West Africa Nei's D found between the savanna and forest samples is 0.04. The savanna population from Zaire is more similar to the savanna one from Mali (D = 0.09) than to the forest one from Ivory Coast (D = 0.13). This appears mainly due to the loci Ldh and Hbdh (possibly linked), some alleles of which seem to be selected for in forest populations (Ldh110, Hbdh108), while others in the savanna ones (Ldh100, Hbdh100). The hypothesis that the discrepant epidemiological patterns of human onchocerciasis are related to intrinsic differences in the parasite seems supported by the obtained data. The differences in allele frequencies found at the reported loci appear strong enough to allow biochemical identification of O. volvulus populations from different geographic regions and different habitats.