101
|
Witte CL, Witte MH, Unger EC, Williams WH, Bernas MJ, McNeill GC, Stazzone AM. Advances in imaging of lymph flow disorders. Radiographics 2000; 20:1697-719. [PMID: 11112825 DOI: 10.1148/radiographics.20.6.g00nv141697] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Conventional oil-contrast lymphography has long been the mainstay for lymphatic imaging. However, the emergence of computed tomography (CT) and magnetic resonance (MR) imaging has severely curtailed its use. Because of recent improvements and refinements, lymphangioscintigraphy now permits high-resolution imaging of peripheral lymphatic vessels and provides insight into lymph flow dynamics. It is indispensable for patients with known or suspected lymphatic circulatory disorders in confirming the diagnosis and delineating the pathogenesis and evolution of lymphedema. In addition, lymphangioscintigraphy helps evaluate lymphatic truncal anatomy and radiotracer transport. It can also be used to evaluate the efficacy of various treatment options designed to facilitate lymph flow or reduce lymph formation. The procedure is essentially noninvasive, can easily be repeated, and does not adversely affect the lymphatic vascular endothelium. MR imaging complements lymphangioscintigraphy in the monitoring and treatment of more complex lymphatic circulatory disorders, whereas CT facilitates catheter-guided percutaneous sclerosis or obliteration of specific lymphangiectasia or lymphangioma syndromes. Ultrasonography has proved useful in the setting of filariasis. Patients with a provisional diagnosis of peripheral lymphatic dysfunction or idiopathic edema should undergo diagnostic lymphangioscintigraphy and, in some cases, MR imaging to verify diagnostic accuracy, pinpoint the specific abnormality, and help guide subsequent therapy.
Collapse
Affiliation(s)
- C L Witte
- Departments of Surgery, University of Arizona College of Medicine, 1501 N Campbell Ave, Rm 4406, PO Box 245063, Tucson, AZ 85724-5063, USA
| | | | | | | | | | | | | |
Collapse
|
102
|
Dissanayake S, Rocha A, Noroes J, Medeiros Z, Dreyer G, Piessens WF. Evaluation of PCR-based methods for the diagnosis of infection in bancroftian filariasis. Trans R Soc Trop Med Hyg 2000; 94:526-30. [PMID: 11132382 DOI: 10.1016/s0035-9203(00)90075-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The value of the polymerase chain reaction (PCR) in the diagnosis of Wuchereria bancrofti infection was evaluated in comparison to microscopical examination of night blood smears, Nuclepore filtration, serology and ultrasonography. No correlation was found between PCR-based deoxyribonucleic acid (DNA) probing and serology. We did not find any evidence of free filarial DNA in either blood plasma or chylocoele fluid. We conclude that the 2 PCR-based techniques evaluated are not more sensitive than Nuclepore filtration for detection of W. bancrofti microfilaraemia, need at least 1 intact microfilaria in the volume of blood used for DNA extraction, and were much inferior to ultrasonography for detection of amicrofilaraemic adult worm carriers.
Collapse
Affiliation(s)
- S Dissanayake
- Department of Microbiology, Faculty of Medicine, UAE University, PO Box 17666, Al Ain, United Arab Emirates.
| | | | | | | | | | | |
Collapse
|
103
|
Dreyer G, Dreyer P. [Rational for morbidity management in bancroftian filariasis endemic areas]. Rev Soc Bras Med Trop 2000; 33:217-21. [PMID: 10881137 DOI: 10.1590/s0037-86822000000200010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Selection of the most appropriate therapy for the patient with bancroftian filariasis requires a knowledge of the diverse clinical characteristics of filarial disease and their pathogenesis. As a result of new diagnostic tests and clinical advances, our understanding of bancroftian filariasis has changed rapidly, as have our ideas about treatment. In the past, it was believed that elephantiasis was caused by an immunologic reaction of the host to the filarial parasite. From this perspective, elephantiasis was seen as the endpoint of an unalterable relationship between the host and the parasite, and given the absence of effective medication or procedures, affected individuals were considered "immunologically predisposed" to this end-stage disease. In the last few years, however, new evidence has suggested that lymphedema and elephantiasis have another etiologic agent. Namely, the principal factor in the evolution of lymphedema and elephantiasis is the involvement of recurrent secondary bacterial infections. Today, it is clear that other forms of supportive therapy (including education and psychological counseling) are necessary and are often more important than antiparasitic drugs.
Collapse
Affiliation(s)
- G Dreyer
- Universidade Federal de Pernambuco, Brasil
| | | |
Collapse
|
104
|
Abstract
There is a growing momentum for the global control and elimination of the major human filariases as public health problems worldwide. The renewed optimism for undertaking this objective reflects the development of simple and potentially cost-effective strategies for mass drug delivery in onchocerciasis and the availability of new extremely effective drug combinations to treat infection, and new methods of morbidity control in lymphatic filariasis. It also reflects the development and current availability of very effective diagnostic, surveillance and control modeling tools for both parasites. Control programming will also be aided by our greater understanding of the biology of transmission, host immunity and disease pathogenesis.
Collapse
Affiliation(s)
- E Michael
- The Wellcome Trust Centre for the Epidemiology of Infectious Disease, University of Oxford, Oxford, UK
| |
Collapse
|
105
|
Richter J, Freise S, Mull R, Millán JC. Fascioliasis: sonographic abnormalities of the biliary tract and evolution after treatment with triclabendazole. Trop Med Int Health 1999; 4:774-81. [PMID: 10588772 DOI: 10.1046/j.1365-3156.1999.00482.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Diagnosis of infection with the liver fluke Fasciola hepatica is usually difficult. Ultrasonography (US) might be a useful diagnostic alternative, and we assessed the value of sequential US in the diagnosis and monitoring of fascioliasis in 76 patients at baseline and for 60 days after treatment with triclabendazole. At baseline, biliary abnormalities were observed in 52 patients. Crescent-shaped parasites were seen in 11 patients; in 2 cases parasites were spontaneously moving and in 4 patients parasites were motionless. Postprandial examination revealed parasites adhering to the gallbladder wall in a further 5 cases. In 3 further cases, gallbladder contents were mobile but did not sediment downwards after patients changed position. Non-specific abnormalities were: impaired gallbladder contractility (n = 23), gallbladder tenderness (n = 19), debris (n = 6), calculi (n = 5), wall thickening (n = 2) and bile duct dilatation (n = 12). During day 1-7, Fasciola-like crescents in the gallbladder or passing through the bile duct were detected in another 15 patients, impaired gallbladder contractility in 16, gallbladder tenderness in 16, and bile duct dilatation in an additional 28 patients. Thirty-two patients with these US abnormalities experienced colic-like abdominal pain accompanied by increased alkaline phosphatase in 25 cases. During day 30-60, abnormalities regressed completely in 45 patients; 2/6 triclabendazole failures were evident by detection of living parasites. Biliary tract abnormalities are frequently observed by US, but the detection-rate of Fasciola hepatica is disappointingly low despite the parasite's relatively large size. US findings must therefore be interpreted together with other clinical measurements. The visualization of parasites being expelled through the dilated common bile duct allowed the causal interpretation of post-therapeutic abdominal pain and increase of liver enzymes. When triclabendazole is given on suspicion, visualization of worm expulsion and bile duct dilatation by US may be used to confirm diagnosis.
Collapse
Affiliation(s)
- J Richter
- Institute of Tropical Medicine, Berlin, Germany
| | | | | | | |
Collapse
|
106
|
Abstract
Human lymphatic filariasis affects 120 million people worldwide. Although the disease is considered to be potentially erradicable by the World Health Organization, comprehensive studies on epidemiological aspects as well as mechanisms of pathology development are still premature. The following review summarizes currently available data on these topics and ends by discussing the latest control strategies.
Collapse
Affiliation(s)
- A B de Almeida
- The University of Alabama at Birmingham, Division of Geographic Medicine, UAB Station, Birmingham, AL 35205, USA
| | | |
Collapse
|
107
|
Dreyer G, Santos A, Noroes J, Addiss D. Proposed panel of diagnostic criteria, including the use of ultrasound, to refine the concept of 'endemic normals' in lymphatic filariasis. Trop Med Int Health 1999; 4:575-9. [PMID: 10499081 DOI: 10.1046/j.1365-3156.1999.00440.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Although living adult Wuchereria bancrofti worms can be detected by ultrasound examination of the scrotal area in approximately 80% of men infected with this filarial parasite, the location of the adult worms in the remaining 20% remains unclear. To determine this, 32 individuals who had W. bancrofti microfilaraemia but no adult worms detectable on ultrasound were treated with diethylcarbarmazine (DEC), either with a single 6 mg/kg dose (n = 13) or with a 12-day course of 6 mg/kg per day (n = 19). They were then monitored with serial physical and ultrasound examinations. Thirteen (41%) subjects developed small, single scrotal nodules 12 h to 7 days after treatment; this rate was unaffected by the dose of DEC. No nodules were detected outside the scrotal area. All 5 men with lymphangiectasia suspected on ultrasound before treatment developed scrotal nodules, compared to 8 (29.6%) of 27 men without ultrasonographic evidence (P = 0.006). Thus, using both ultrasound and 'provocative' treatment with DEC, adult W. bancrofti can be detected in the scrotal area of an estimated 88% of infected men. Because no single diagnostic test for W. bancrofti infection is completely sensitive, a panel of tests, including ultrasound, is proposed to identify with greater accuracy 'endemic normals' for immunological and epidemiological studies.
Collapse
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Centro de Pesquisas Aggeu Magalhaes-FIOCRUZ, Universidade Federal de Pernambuco, Recife, Brazil
| | | | | | | |
Collapse
|
108
|
Peixoto CA, Norões J, Rocha A, Dreyer G. Immunocytochemical localization and distribution of human albumin in Wuchereria bancrofti adult worms. Arch Pathol Lab Med 1999; 123:173-7. [PMID: 10050796 DOI: 10.5858/1999-123-0173-iladoh] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
To determine whether albumin is present on adult worms of Wuchereria bancrofti, thin sections of resin-embedded parasites were incubated with a specific antiserum to human albumin. With the exception of the epicuticle, all layers of the cuticle and the hypodermis were intensely labeled. Concentration of gold particles was observed within infoldings of the hypodermal membrane. Moderate labeling of the thin basement membrane that lines the pseudocelomic cavity and the gonoduct was also observed. Within the uterus, ovular membranes labeled intensely; groups of organized particles were seen below ovular membranes and also within invaginations of microfilarial embryos. In contrast, few gold particles were seen on the surface of mature intrauterine microfilariae. No labeling was observed in control sections incubated with antiserum preadsorbed with purified human albumin. The findings suggest that human albumin may be essential for the nutrition and development of W bancrofti microfilariae.
Collapse
Affiliation(s)
- C A Peixoto
- Department of Pathology and Cellular Biology, Centro de Pesquisas Aggeu Magalhães, Universidade Federal de Pernambuco, Recife, Brazil
| | | | | | | |
Collapse
|
109
|
Marchetti F, Piessens WF, Medeiros Z, Dreyer G. Abnormalities of the leg lymphatics are not specific for bancroftian filariasis. Trans R Soc Trop Med Hyg 1998; 92:650-2. [PMID: 10326111 DOI: 10.1016/s0035-9203(98)90797-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
Studies using conventional angiography or non-invasive scintigraphy have revealed widespread abnormalities in the lymphatics of the legs of patients with bancroftian filariasis, regardless of whether clinical lymphoedema is present. To determine if the observed changes were specific for filarial infections, we imaged the lymphatics of both legs in native residents of an area in Brazil where filariasis is not endemic. Study participants were matched by age, socioeconomic status and physical activities to patients with filariasis in Recife, evaluated in parallel. Based on textbook criteria, only one of 15 study participants had a completely normal lymphoscintigram. Modest to severe pathology of the leg lymphatics was observed in the remaining 14 residents of the non-endemic area and in 49 of 50 patients with bancroftian filariasis. These results indicated that factors other than filarial worms are a common cause of subclinical pathology of the leg lymphatics in north-eastern Brazil, and that the latter is not specific for bancroftian filariasis.
Collapse
Affiliation(s)
- F Marchetti
- Hospital das Clinicas, Universidade Federal de Pernambuco, Recife, Brazil
| | | | | | | |
Collapse
|
110
|
MacDonald AS, Maizels RM, Lawrence RA, Dransfield I, Allen JE. Requirement for In Vivo Production of IL-4, But Not IL-10, in the Induction of Proliferative Suppression by Filarial Parasites. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.8.4124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Loss of T lymphocyte proliferation and the emergence of a host response that is dominated by a Th2-type profile are well-established features of human filariasis. We have previously reported that adherent peritoneal exudate cells (PEC) from mice transplanted with adult Brugia malayi parasites suppress the proliferation of lymphocytes without blocking Ag-cytokine production in vitro. We now show that infection of mice with the infective larval (L3) stage of B. malayi generates a similar population of PEC. Suppressive cells are generated within 7 days of infection and mediate their effects through a nitric oxide-independent pathway. Both L3 and adult infection elicit high levels of host IL-4 whereas the microfilarial stage of the parasite induces IFN-γ production and does not generate a similar form of suppression. Production of host IL-4 was necessary to allow the generation of suppressive PEC, given that IL-4-deficient mice implanted with adult parasites failed to induce proliferative block. However, IL-10-deficient mice implanted with adult parasites resulted in T cell suppression, indicating that IL-10 is not essential for the induction of hyporesponsiveness. Neither IL-4 nor IL-10 were directly responsible for ablating cellular proliferation in vitro, as the addition of neutralizing Ab to either cytokine did not reverse the proliferative block. Thus, IL-4 produced in vivo in response to filarial L3 and adult parasites is essential for the induction of proliferative suppression but is not itself the suppressive factor.
Collapse
Affiliation(s)
- Andrew S. MacDonald
- *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, U.K.
| | - Rick M. Maizels
- *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, U.K.
| | - Rachel A. Lawrence
- †Department of Biology, Imperial College of Science, Technology and Medicine, London; and
| | - Ian Dransfield
- ‡The Rayne Laboratory, Medical School, University of Edinburgh, Edinburgh, United Kingdom
| | - Judith E. Allen
- *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, U.K.
| |
Collapse
|
111
|
Dreyer G, Addiss D, Santos A, Figueredo-Silva J, Norões J. Direct assessment in vivo of the efficacy of combined single-dose ivermectin and diethylcarbamazine against adult Wuchereria bancrofti. Trans R Soc Trop Med Hyg 1998; 92:219-22. [PMID: 9764338 DOI: 10.1016/s0035-9203(98)90754-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
When ivermectin and diethylcarbamazine (DEC) are given simultaneously in a single dose to persons with Wuchereria bancrofti infection, the resulting suppression of microfilaraemia is more profound and sustained than when either drug is given alone. To assess whether this effect is a result of enhanced macrofilaricidal efficacy, we used ultrasound to monitor the adult worms in the scrotal area of men with W. bancrofti microfilaraemia. Twenty-one men were treated simultaneously with DEC (6 mg/kg) and either 200 micrograms/kg or 400 micrograms/kg of ivermectin (11 and 10 men, respectively). Ten other men received a single 200 micrograms/kg dose of ivermectin followed 5 d later by a 6 mg/kg dose of DEC (sequential treatment). All men became amicrofilaraemic after treatment and all except one remained so for one year. Cessation of adult worm movement, indicative of death of all the adult worms in a given 'nest', was observed in none of 30 nests in men who received simultaneous treatment and in 3 of the 19 nests (16%) in the men who received sequential treatment (P = 0.05). Scrotal nodules were detected in 5 of 21 men (24%) who received simultaneous treatment and in 8 men (80%) who received sequential treatment (P < 0.01). Thus, co-administration of ivermectin with DEC seems to interfere with the macrofilaricidal action of DEC. These findings have implications both for treatment of the individual patient and for community-based drug distribution programmes designed to interrupt transmission of W. bancrofti.
Collapse
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Centro de Pesquisas Aggeu Magalhaes-FIOCRUZ, Recife, PE, Brazil
| | | | | | | | | |
Collapse
|
112
|
MacDonald AS, Maizels RM, Lawrence RA, Dransfield I, Allen JE. Requirement for In Vivo Production of IL-4, But Not IL-10, in the Induction of Proliferative Suppression by Filarial Parasites. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.160.3.1304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Loss of T lymphocyte proliferation and the emergence of a host response that is dominated by a Th2-type profile are well-established features of human filariasis. We have previously reported that adherent peritoneal exudate cells (PEC) from mice transplanted with adult Brugia malayi parasites suppress the proliferation of lymphocytes without blocking Ag-cytokine production in vitro. We now show that infection of mice with the infective larval (L3) stage of B. malayi generates a similar population of PEC. Suppressive cells are generated within 7 days of infection and mediate their effects through a nitric oxide-independent pathway. Both L3 and adult infection elicit high levels of host IL-4 whereas the microfilarial stage of the parasite induces IFN-γ production and does not generate a similar form of suppression. Production of host IL-4 was necessary to allow the generation of suppressive PEC, given that IL-4-deficient mice implanted with adult parasites failed to induce proliferative block. However, IL-10-deficient mice implanted with adult parasites resulted in T cell suppression, indicating that IL-10 is not essential for the induction of hyporesponsiveness. Neither IL-4 nor IL-10 were directly responsible for ablating cellular proliferation in vitro, as the addition of neutralizing Ab to either cytokine did not reverse the proliferative block. Thus, IL-4 produced in vivo in response to filarial L3 and adult parasites is essential for the induction of proliferative suppression but is not itself the suppressive factor.
Collapse
Affiliation(s)
- Andrew S. MacDonald
- *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, U.K.
| | - Rick M. Maizels
- *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, U.K.
| | - Rachel A. Lawrence
- †Department of Biology, Imperial College of Science, Technology and Medicine, London; and
| | - Ian Dransfield
- ‡The Rayne Laboratory, Medical School, University of Edinburgh, Edinburgh, United Kingdom
| | - Judith E. Allen
- *Institute of Cell, Animal and Population Biology, University of Edinburgh, Edinburgh, U.K.
| |
Collapse
|
113
|
Michael E, Grenfell BT, Isham VS, Denham DA, Bundy DA. Modelling variability in lymphatic filariasis: macrofilarial dynamics in the Brugia pahangi--cat model. Proc Biol Sci 1998; 265:155-65. [PMID: 9474798 PMCID: PMC1688862 DOI: 10.1098/rspb.1998.0277] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
A striking feature of lymphatic filariasis is the considerable heterogeneity in infection burden observed between hosts, which greatly complicates the analysis of the population dynamics of the disease. Here, we describe the first application of the moment closure equation approach to model the sources and the impact of this heterogeneity for macrofilarial population dynamics. The analysis is based on the closest laboratory equivalent of the life cycle and immunology of infection in humans--cats chronically infected with the filarial nematode Brugia pahangi. Two sets of long-term experiments are analysed: hosts given either single primary infections or given repeat infections. We begin by quantifying changes in the mean and aggregation of adult parasites (inversely measured by the negative binomial parameter, kappa in cohorts of hosts using generalized linear models. We then apply simple stochastic models to interpret observed patterns. The models and empirical data indicate that parasite aggregation tracks the decline in the mean burden with host age in primary infections. Conversely, in repeat infections, aggregation increases as the worm burden declines with experience of infection. The results show that the primary infection variability is consistent with heterogeneities in parasite survival between hosts. By contrast, the models indicate that the reduction in parasite variability with time in repeat infections is most likely due to the 'filtering' effect of a strong, acquired immune response, which gradually acts to remove the initial variability generated by heterogeneities in larval mortality. We discuss this result in terms of the homogenizing effect of host immunity-driven density-dependence on macrofilarial burden in older hosts.
Collapse
Affiliation(s)
- E Michael
- Department of Zoology, University of Oxford, UK
| | | | | | | | | |
Collapse
|
114
|
Affiliation(s)
- I J Dunn
- Department of Radiology, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
115
|
Fleming-Hübertz S, Simonsen PE, Jensen LT. Circulating connective tissue metabolites in patients with bancroftian filariasis. Trans R Soc Trop Med Hyg 1997; 91:442-5. [PMID: 9373649 DOI: 10.1016/s0035-9203(97)90277-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Sera from adults from an area of Tanzania with high endemicity for Wuchereria bancrofti infection were examined for 4 serological markers of extracellular matrix activity, namely the amino-terminal propeptide of type III procollagen (PIIINP), the carboxy-terminal propeptide of type I procollagen (PICP), the carboxy-terminal telopeptide of type I collagen (ICTP), and hyaluronan. Sera from individuals with non-filarial elephantiasis and from healthy Danes were included as controls. No association was observed between the mean serum concentration of PIIINP or PICP and the clinical, microfilarial or circulating filarial antigen status of the individuals. The mean concentration of ICTP was significantly higher (P < 0.01) in sera from individuals with filarial and non-filarial elephantiasis than in sera from individuals living in filariasis endemic areas but without elephantiasis or in the Danish control sera. Among individuals from the filariasis endemic area, the mean serum concentration of hyaluronan was significantly higher (P < 0.01) in microfilaraemic than in amicrofilaraemic individuals, and significantly higher (P < 0.01) in individuals who had circulating filarial antigens than in those who did not, but there was no relation to the clinical status. The significance of the findings are discussed in relation to the pathological processes taking place in bancroftian filariasis.
Collapse
|
116
|
Abstract
The authors presented a detailed review about the treatment of bancroftian filariasis with diethylcarbamazine. The interesting aspects about the drug discovery and the basic concepts about its pharmacology were reported in a summarised form. On the other hand, emphasis was made about the speculation done by several authors about the intriguing findings regarding its efficacy reported in the literature. Latter, it was brought the new advances about the disease, as for example, the visualization by ultrasound of living Wuchereria bancrofti adult worm on its natural host--the human being. This made possible the comprehension of several paradoxical issues reported, focusing the treatment of infection using diethylcarbamazine. So far, because of the lack of ideal drug with micro and macrofilaricidal properties, together with the new understand about the disease and the new parameters for monitoring the efficacy of the drug, diethylcarbamazine has back its importance conquered at the begin of its discovery, almost fifth years ago.
Collapse
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Universidade Federal de Permambuco, Recife, PE, Brasil
| | | |
Collapse
|
117
|
Dreyer G, Norões J, Addiss D. The silent burden of sexual disability associated with lymphatic filariasis. Acta Trop 1997; 63:57-60. [PMID: 9083585 DOI: 10.1016/s0001-706x(96)00604-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Centro de Pesquisas Aggeu Magalhaes-FIOCRUZ, Recife, Brasil
| | | | | |
Collapse
|
118
|
Norões J, Dreyer G, Santos A, Mendes VG, Medeiros Z, Addiss D. Assessment of the efficacy of diethylcarbamazine on adult Wuchereria bancrofti in vivo. Trans R Soc Trop Med Hyg 1997; 91:78-81. [PMID: 9093637 DOI: 10.1016/s0035-9203(97)90405-3] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
To assess directly the effect of various doses of diethylcarbamazine (DEC) on adult Wuchereria bancrofti, 31 infected men were randomly assigned to receive an initial single DEC dose of 1 mg/kg (n = 7), 6 mg/kg (n = 10), or 12 mg/kg (n = 14). Beginning 7 d later, the dosage of DEC and duration of treatment were progressively increased for 7-10 weeks. Physical examinations were performed to detect scrotal nodules and the scrotal area was examined by ultrasound (7.5 MHz transducer) to monitor the 'filaria dance sign' (FDS), the characteristic pattern of adult worm movement. Of 53 adult worm 'nests' that were detected by ultrasound, 22 (41.5%) were DEC-sensitive (FDS became non-detectable and a nodule became palpable at the site); 20 (37.7%) were not sensitive (FDS remained unchanged and detectable and no nodule developed), and 11 (20.8%) showed mixed responses (FDS remained detectable but a palpable nodule developed). All but one sensitive or mixed response occurred within 1 week after the initial single dose. Of 39 'nests' in men who initially received a single 6 or 12 mg/kg dose of DEC, 20 (51.3%) had sensitive responses compared to 2 (14.3%) of 14 'nests' in men who received a single 1 mg/kg dose (P = 0.04). Above 6 mg/kg, the macrofilaricidal effect of DEC did not increase with dose; a significant proportion of adult W. bancrofti were not susceptible to DEC during the study period.
Collapse
Affiliation(s)
- J Norões
- Servico de Urologia, Hospital das Clinicas, Universidade Federal de Pernambuco, Recife, Brazil
| | | | | | | | | | | |
Collapse
|
119
|
Witte MH, Way DL, Witte CL, Bernas M. Lymphangiogenesis: mechanisms, significance and clinical implications. EXS 1997; 79:65-112. [PMID: 9002221 DOI: 10.1007/978-3-0348-9006-9_5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- M H Witte
- Department of Surgery, University of Arizona College of Medicine, Tucson 85724, USA
| | | | | | | |
Collapse
|
120
|
Abstract
Genital presentation of filarial disease is not uncommon in endemic areas of the world. Acute, febrile illness involving the epididymis and spermatic cord (funiculoepididymitis) is one of many such presentations. With an internationally mobile society, physicians today, even in nonendemic areas, may encounter patients with filarial infestations. We report the first case of presumptive diagnosis of this disease using scrotal ultrasound.
Collapse
Affiliation(s)
- P B Williams
- Department of Urology, Louisiana State University Medical Center, Shreveport, USA
| | | | | | | |
Collapse
|
121
|
Norões J, Addiss D, Santos A, Medeiros Z, Coutinho A, Dreyer G. Ultrasonographic evidence of abnormal lymphatic vessels in young men with adult Wuchereria bancrofti infection in the scrotal area. J Urol 1996; 156:409-12. [PMID: 8683691 DOI: 10.1097/00005392-199608000-00019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
PURPOSE We determined the prevalence and magnitude of dilatation of the lymphatic vessels of the spermatic cord in men infected with Wuchereria bancrofti, which is known major cause of hydrocele in the tropics. MATERIALS AND METHODS Scrotal ultrasound was performed with a 7.5 MHz, transducer in 78 men from Recife, Brazil (endemic for filariasis) and in 15 from a nonendemic area. RESULTS Among men from Recife the lymphatic vessels were dilated (1.3 to 15.0 mm., mean 3.8) at the location of the adult worm. Vessel diameter was not associated with hydrocele. CONCLUSIONS Lymphatic dilation was observed in all men with ultrasonographically detectable W. bancrofti infection, even those who were asymptomatic.
Collapse
Affiliation(s)
- J Norões
- Hospital das Clinicas, UFPE, Centro de Pesquisas Aggeu Magalhaes-FIOCRUZ, Recife, Brasil
| | | | | | | | | | | |
Collapse
|
122
|
Dreyer G, Addiss D, Noroes J, Amaral F, Rocha A, Coutinho A. Ultrasonographic assessment of the adulticidal efficacy of repeat high-dose ivermectin in bancroftian filariasis. Trop Med Int Health 1996; 1:427-32. [PMID: 8765448 DOI: 10.1046/j.1365-3156.1996.d01-79.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Since diethylcarbamazine, the drug recommended for treatment of lymphatic filariasis, seems only partially effective against the adult worm, intense interest persists in identifying a macrofilaricidal drug for this infection. To evaluate directly in vivo the macrofilaricidal activity of repeat high-dose ivermectin, 15 men who had living adult Wuchereria bancrofti detected in the scrotal area by ultrasound were treated with 400 micrograms/kg of ivermectin at 2-week intervals for 6 months (total dose, 4.8 mg/kg). Serial ultrasound examinations were performed before, during, and for 6 months after treatment. Profound suppression of microfilaraemia followed the first dose of ivermectin, but movements characteristic of the adult worm on ultrasound remained unchanged both in location and pattern. Even when given in total doses of 4.8 mg/kg, ivermectin appears to have no observable activity against adult W. bancrofti, although its ability to suppress microfilaraemia makes it potentially useful for the control of lymphatic filariasis.
Collapse
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Centro de Pesquisas Aggeu Magalhäes-FIOCRUZ, Recife, Brazil
| | | | | | | | | | | |
Collapse
|
123
|
Dreyer G, Santos A, Norões J, Rocha A, Addiss D. Amicrofilaraemic carriers of adult Wuchereria bancrofti. Trans R Soc Trop Med Hyg 1996; 90:288-9. [PMID: 8758079 DOI: 10.1016/s0035-9203(96)90253-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
To determine the extent to which Wuchereria bancrofti infections can be detected in asymptomatic amicrofilaraemic men in Greater Recife, Brazil, we studied 100 asymptomatic men who were long-term residents (> or = 15 years) of this filariasis-endemic area and who were amicrofilaraemic in 60 microL of capillary blood collected at night. Increasing amounts (1, 5, and 10 mL) of venous blood were collected in consecutive weeks, filtered, and examined for microfilariae; 27 men were eventually found to be microfilariaemic and 10 remained amicrofilaraemic but were found to be carriers of living adult W. bancrofti by ultrasound examination of the scrotal area. Thus, 37% of 'amicrofilaraemic' men (in 60 microL of blood) were found to be infected by more thorough investigation. Ultrasound is a valuable tool to identify adult worm infections in amicrofilaraemic persons, particularly for evaluation of serological assays and immunological studies in which the distinction between 'amicrofilaraemic adult worm carriers' and 'endemic normal subjects' is critical.
Collapse
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Cidade Universitaria, Recife, PE, Brazil
| | | | | | | | | |
Collapse
|
124
|
Norões J, Addiss D, Amaral F, Coutinho A, Medeiros Z, Dreyer G. Occurrence of living adult Wuchereria bancrofti in the scrotal area of men with microfilaraemia. Trans R Soc Trop Med Hyg 1996; 90:55-6. [PMID: 8730313 DOI: 10.1016/s0035-9203(96)90478-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
To determine the frequency with which living adult Wuchereria bancrofti can be detected by ultrasound in the scrotal area of men with filarial infection, we used a 7.5 MHz transducer to perform weekly ultrasound examinations on 100 microfilaraemic men (18-34 years old) from Greater Recife, Brazil. The peculiar pattern of movement that characterizes the adult worm image on ultrasound (the filaria dance sign) was detected in the lymphatic vessels of the spermatic cord in 80 men (bilaterally in 29 men). Among 20 men with no filaria dance sign, the geometric mean microfilarial density was 68/mL, compared with 238/mL and 775/mL among those with unilateral and bilateral filaria dance signs, respectively (P = 0.0001). The lymphatic vessels of the spermatic cord appear to be a common, and perhaps the principal, site of adult W. bancrofti in men with asymptomatic microfilaraemia. Studies are needed to define the relationship between the presence of filarial worms in the scrotal area and the development of filaria-associated morbidity.
Collapse
Affiliation(s)
- J Norões
- Hospital das Clinicas, Universidade Federal de Pernambuco, Recife, Brazil
| | | | | | | | | | | |
Collapse
|
125
|
Dissanayake S, Watawana L, Piessens WF. Lymphatic pathology in Wuchereria bancrofti microfilaraemic infections. Trans R Soc Trop Med Hyg 1995; 89:517-21. [PMID: 8560529 DOI: 10.1016/0035-9203(95)90092-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
To determine the extent of lymphatic disease in persons infected with Wuchereria bancrofti who were microfilaraemic, we examined the superficial lymphatics of the legs by scintigraphy. In 4 endemic control subjects and in 10 of 14 clinically asymptomatic microfilaraemic individuals, lymphoscintigraphy revealed one major channel of lymphatic drainage in each leg. However, while trunk lymphatics were bilaterally symmetrical in the control, marked differences in the calibre of lymphatic vessels were observed in the microfilaraemic persons. Non-discrete lymphatics and a diffuse symmetrical distribution of collateral vessels in both legs were observed in all of 5 amicrofilaraemic patients with grade 2 lymphoedema. A similar diffuse drainage pattern was also seen in 3 previously microfilaraemic persons who had remained amicrofilaraemic and asymptomatic following treatment with diethylcarbamazine citrate (DEC). Thus, clearance of microfilaraemia by DEC therapy did not appear to reverse the type of lymphatic pathology observed in microfilaraemic subjects. The lymphoscintigraphy patterns did not correlate with serum levels of antibodies to 3 recombinant filarial antigens. Virtually all the asymptomatic microfilaraemic individuals infected with W. bancrofti examined had subclinical lymphatic disease detected by the non-invasive imaging technique of lymphoscintigraphy.
Collapse
Affiliation(s)
- S Dissanayake
- Harvard School of Public Health, Boston, MA 02115, USA
| | | | | |
Collapse
|
126
|
Dreyer G, Noroes J, Amaral F, Nen A, Medeiros Z, Coutinho A, Addiss D. Direct assessment of the adulticidal efficacy of a single dose of ivermectin in bancroftian filariasis. Trans R Soc Trop Med Hyg 1995; 89:441-3. [PMID: 7570894 DOI: 10.1016/0035-9203(95)90049-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Although the potent microfilaricidal activity of ivermectin is well established, its efficacy against adult Wuchereria bancrofti is unknown. We used longitudinal ultrasound examinations for periods of 3-9 months to assess directly the macrofilaricidal effect of a single 400 micrograms/kg dose of ivermectin in 15 men from Recife, Brazil who were infected with W. bancrofti. Before treatment, microfilarial densities ranged from 3 to 3098 microfilariae per mL of blood, and movements characteristic of the living adult worm (the 'filaria dance sign') were observed by ultrasound examination of the scrotal lymphatic vessels in all 15 men. Following treatment, microfilarial density was markedly reduced in all men, but the filaria dance sign remained unchanged in both location and pattern. Eight months after treatment, a dilated lymphatic vessel was surgically removed from one patient at the site of the filaria dance sign, and 3 intact adult worms were released. When given as a single 400 micrograms/kg dose, ivermectin had no observable effect on adult W. bancrofti. Therefore, prolonged suppression of microfilaraemia following treatment with ivermectin cannot be explained by a macrofilaricidal effect of the drug. Ultrasound is a valuable new tool for directly and rapidly assessing the macrofilaricidal efficacy of antifilarial drugs in lymphatic filariasis.
Collapse
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, CPqAM-FIOCRUZ, Recife, Brazil
| | | | | | | | | | | | | |
Collapse
|
127
|
Albuquerque MF, Marzochi MC, Sabroza PC, Braga MC, Padilha T, Silva MC, Silva MR, Schindler HC, Maciel MA, Souza W. Bancroftian filariasis in two urban areas of Recife, Brazil: pre-control observations on infection and disease. Trans R Soc Trop Med Hyg 1995; 89:373-7. [PMID: 7570866 DOI: 10.1016/0035-9203(95)90014-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Bancroftian filariasis is a major public health problem in the city of Recife in north-eastern Brazil. In some of its urban areas microfilaraemia prevalence reaches 14%. This study describes epidemiological characteristics, infection and disease, in 2 urban areas, Coque and Mustardinha, before control measures were applied. The parasitological survey was performed by a 'door-to-door' census covering 5563 subjects, aged between 5 and 65 years. Microfilaraemia was detected by the thick drop technique, using 45 microL of peripheral blood collected between 20:00 and 24:00. In both areas the prevalence of microfilaraemia was 10%, and males had higher prevalences of infection and disease than females. The prevalence of microfilaraemia was higher in the 15-24 and 25-34 years age groups in both sexes. Most microfilaria (mf) carriers (72.1% in Coque and 79.7% in Mustadrinha) had mf densities < 100/60 microL of blood. Females of reproductive age had significantly lower mf densities than males. The overall disease prevalence in both areas was 6.3%. Amongst the subjects who presented with chronic disease 15.7% were microfilaraemic. Chronic disease prevalence increased from 1.4% in the 5-14 years age group to 11.3% in the oldest age group. The most frequent clinical manifestation was hydrocele (5.4%), followed by lymphoedema (1.8%). The epidemiological pattern of filariasis in the populations studied was marked by high prevalence of microfilaraemia, low mf density, and relatively low prevalence of filarial disease considering the level of endemicity.
Collapse
Affiliation(s)
- M F Albuquerque
- Centro de Pesquisas Aggeu Magalhães, Fundação Oswaldo Cruz, Universidade Federal de Pernambuco, Recifè, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
128
|
Araujo A, Souto-Padron T, de Souza W. Ultrastructural and cytochemical aspects of the cuticle of adult Wuchereria bancrofti (Nematoda: Filarioidea). Int J Parasitol 1995; 25:569-77. [PMID: 7543460 DOI: 10.1016/0020-7519(94)00167-m] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Because of the practical limitations of obtaining viable adult forms of the Wuchereria bancrofti, the major species responsible for human lymphatic filariasis, only few ultrastructural studies were carried out. Adult worms present the cuticle as the interface structure between host and parasite. Cuticle structure and the demonstration of the presence of basic proteins, lipids, small amounts of terminal carbohydrate residues, phospholipids and collagen in the cuticle was undertaken on thin sections of embedded parasites. Using immunocytochemical methods, antigenic epitopes similar to those found in the extra cellular matrix of vertebrates were localized on thin sections of the Lowicryl embedded adult filariae.
Collapse
Affiliation(s)
- A Araujo
- Laboratorio de Ultraestrutura Celular Hertha Meyer, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil
| | | | | |
Collapse
|
129
|
Dreyer G, Amaral F, Norões J, Medeiros Z, Addiss D. A new tool to assess the adulticidal efficacy in vivo of antifilarial drugs for bancroftian filariasis. Trans R Soc Trop Med Hyg 1995; 89:225-6. [PMID: 7778157 DOI: 10.1016/0035-9203(95)90506-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Affiliation(s)
- G Dreyer
- Departamento de Parasitologia, Centro de Pesquisas Aggeu Magalhães/FIOCRUZ, Recife, Pernambuco, Brasil
| | | | | | | | | |
Collapse
|
130
|
Dreyer G, Coutinho A, Miranda D, Noroes J, Rizzo JA, Galdino E, Rocha A, Medeiros Z, Andrade LD, Santos A. Treatment of bancroftian filariasis in Recife, Brazil: a two-year comparative study of the efficacy of single treatments with ivermectin or diethylcarbamazine. Trans R Soc Trop Med Hyg 1995; 89:98-102. [PMID: 7747322 DOI: 10.1016/0035-9203(95)90674-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The effectiveness of single oral doses of ivermectin (200 or 400 micrograms/kg) and diethylcarbamazine (DEC, 6 mg/kg), preceded 4 d earlier by either placebo or very small doses of these drugs, was compared, over a 2-year period, in a double-blind trial in 67 microfilaraemic Brazilian men with bancroftian filariasis. Regimens containing ivermectin alone decreased the number of microfilariae significantly faster and more effectively for the first month after treatment than regimens containing DEC alone, but the latter were significantly more effective throughout the second year after treatment (1.7-8.2% of pretreatment levels with DEC vs. 12.6-30.8% with ivermectin during that period); the higher ivermectin dose showed a tendency towards more effectiveness than the lower dose. Most effective was the combination of ivermectin (20 micrograms/kg) followed 4 d later by DEC (6 mg/kg), with reduction of microfilaraemia to 2.4% of pretreatment levels at 2 years. Adverse reactions were well tolerated with all regimens, the reactions being significantly more generalized (i.e., fever) following ivermectin and localized (i.e., scrotal inflammatory nodules around dying adult worms) following DEC. Further trials of single-dose combination therapy vs. single high doses of ivermectin or DEC should determine the ideal regimen for treatment and control of bancroftian filariasis.
Collapse
Affiliation(s)
- G Dreyer
- Centro de Pesquisas Aggeu Magalhaes/FIOCRUZ, Recife, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
131
|
Dreyer G, Amaral F, Noroes J, Medeiros Z. Ultrasonographic evidence for stability of adult worm location in bancroftian filariasis. Trans R Soc Trop Med Hyg 1994; 88:558. [PMID: 7992338 DOI: 10.1016/0035-9203(94)90162-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Affiliation(s)
- G Dreyer
- Centro de Pesquisas Aggeu Magalhães-Fiocruz, Recife, Pernambuco, Brazil
| | | | | | | |
Collapse
|