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H J Engelkens

Publications and source records attributed to H J Engelkens.

At least 19 recordsLinked to original sources
PubMed1998

[The pathophysiology and treatment of cholestatic pruritus].

Pruritus is a frequent, distressing and sometimes disabling symptom of liver and biliary tract disorders. Results of treatment are sometimes disappointing and the pathophysiology is still largely unknown. It was recently discovered that endogenous opioids contribute to the perception of itching and that opiate receptor antagonists can reduce the overstimulation of these receptors and thereby attenuate the itching. A stepwise treatment strategy focusing successively on ion exchange resins, rifampicin and opiate receptor antagonists leads to effective alleviation of itching in most patients.

Cholestasis↗
PubMed1996

Hepatitis in a patient with SLE: is it autoimmune hepatitis?

In a patient with systemic lupus erythematosus (SLE), we considered the diagnosis of autoimmune hepatitis (AIH) in view of raised serum aminotransferases, hypergammaglobulinaemia, antinuclear antibodies (titre 1:10,240), seronegativity of markers for viral hepatitis and absence of recent hepatotoxic drug usage. The diagnosis of AIH was supported by using the scoring system, recently developed by the International Autoimmune Hepatitis Group and the excellent response to treatment with prednisone. Liver histology, however, showed no characteristic features of AIH. The relevance of liver histology and scoring for AIH in SLE with hepatic involvement is discussed.

Adult↗
PubMed1994

Mycetoma.

Explore the source record for details and available documents.

Combined Modality Therapy↗
PubMed1993

The localisation of treponemes and characterisation of the inflammatory infiltrate in skin biopsies from patients with primary or secondary syphilis, or early infectious yaws.

OBJECTIVE: To study the localisation of treponemes and to analyse the inflammatory infiltrate in biopsy specimens from patients with primary or secondary syphilis, or early infectious yaws. MATERIALS AND METHODS: Skin biopsies originating from human lesions of primary (29x) or secondary (15x) syphilis (Rotterdam), or early yaws (18x) (West Sumatra) were studied. Different histochemical and immunohistochemical detection methods were used in this study. RESULTS AND CONCLUSION: The histochemical silver staining method according to Steiner revealed the presence of T. pallidum in all cases of primary syphilis studied. In 10 out of 14 cases of secondary syphilis, treponemes were demonstrated. With an immunofluorescence staining technique (IF) using anti-T. pallidum antiserum raised in rabbits (a-Tp), T. pallidum was demonstrated in 28 out of 29 cases of primary syphilis, and in 14 out of 14 studied cases of secondary syphilis. The silver staining method and IF showed identical localisations of T. pallidum (mainly in the dermal-epidermal junction zone or throughout the dermis). Using a-Tp antiserum in the indirect immunofluorescence technique, T. pertenue could be demonstrated in the dermis more often than with Steiner silver staining. However, epidermotropism of T. pertenue in yaws specimens was remarkable, compared with more mesodermotropism of T. pallidum; numbers of T. pertenue in the dermis were limited in all specimens. The dermal inflammatory infiltrate in primary and secondary syphilis was composed mainly of lymphocytes and plasma cells. In most cases more T (CD3 positive) cells than B (CD22 positive) cells were present. Regarding T cell subpopulations, in primary syphilis, T helper/inducer (CD4 positive) cells predominated in 86% of cases. In secondary syphilitic lesions, numbers of T helper/inducer cells were less frequent than or equal to T-suppressor/cytotoxic (CD8 positive) cells in 60% of cases. Remarkably, in yaws specimens the inflammatory infiltrate consisted mainly of IgG, but also IgA and IgM producing plasma cells. T or B lymphocytes were scarce, which is in sharp contrast with findings in syphilitic lesions.

Adolescent↗
PubMed1993

The importance of different components of normal human serum and lysozyme in the rapid immobilisation of purified Treponema pallidum, Nichols strain.

OBJECTIVES: To study the role of different components in normal human serum and the role of lysozyme in rapid immobilisation of Percoll purified T pallidum (Nichols). MATERIALS AND METHODS: The immobilisation of Percoll purified T pallidum was studied after pre-incubations with different serum fractions (Fr) of normal human serum (Fr 1, containing IgM; Fr 2, containing IgG and a low level of haemolytic complement, and Fr 1 (abs), depleted of IgG). A guinea-pig serum pool was used as a complement source in the immobilisation experiments. The influence was studied of removal of lysozyme from guinea-pig serum on the immobilisation reactions. Further experiments were performed, using a fluorescence technique, to detect C3b depositions on fixed treponemes and treponemes in suspension. RESULTS: Rapid immobilisation of Percoll-purified treponemes by the NHS serum fractions occurred only after preincubation with Fr 1 and Fr 2 simultaneously. This was largely dependent on the presence of a small amount of haemolytic C in Fr 2. Removal of lysozyme reduced this rapid rate of immobilisation. In fluorescence experiments it was demonstrated that C3b deposition on fixed (that is damaged) treponemes occurred upon their incubation with Fr 2 or the combination of Fr 1 and 2. However, on treponemes in suspension C3b deposition occurred only after incubation with the combination of Fr 1 and 2. CONCLUSION: The rapid immobilisation of Percoll purified treponemes by serum fractions from normal human serum requires antibodies of the IgM and IgG class, together with complement and lysozyme. Omission of one of these reactants slows immobilisation. Our experiments suggest that the reactants act in sequence: the loss of integrity of the outer membrane by an attack by IgM and C offers the opportunity for lysozyme to hydrolyse the peptidoglycan layer surrounding the cytoplasmic membrane of the treponemes, which then is accessible for attack by antibodies and C.

Animals↗
PubMed1992

Case report 724. Yaws.

A 15-year-old girl presented with the typical clinical, serological, and pathological lesions of yaws. The patient was a native of Sumatra. The important diagnostic criteria and the relationship to venereal syphilis were discussed.

Adolescent↗
PubMed1992

The influence of different sera on the in vitro immobilisation of Percoll purified Treponema pallidum, Nichols strain.

OBJECTIVES: Investigation of sera, especially rabbit serum, in preventing in vitro immobilisation of Percoll purified T. pallidum. MATERIALS AND METHODS: The immobilisation of Percoll purified T. pallidum (Nichols) was studied after pre-incubations with basal reduced medium (BRM), heat-inactivated serum of seven different species of animals, heat-inactivated normal human serum (NHS) and rabbit sera containing a different level of antitreponemal antibodies. Also increasing percentages of heat-inactivated normal rabbit serum (NRS) were studied. RESULTS: The rapid immobilisation of purified treponemes by NHS is delayed by pre-incubation with NRS in a dose-dependent manner. The treponemes from 5-day infections were immobilised significantly more slowly than treponemes from 7- and 8-day infections. Compared with NRS, pre-incubations with a high-titred, low-titred and "autologous" serum resulted in significantly more rapid immobilisation of the treponemes. With most other animal sera resistance to immobilisation was slight compared with that produced by NRS. Immunofluorescent studies revealed that the treponemes were covered with a layer of the human third complement factor (C3b), within an hour of incubation. With two sequential pre-incubations, a delay of the immobilisation was only noted in those test mixtures in which NRS had been present in both preincubations. CONCLUSION: Rabbit serum delays the rapid in vitro immobilisation of Percoll purified treponemes by normal human serum. There was no evidence that this was caused by preventing access of antibodies (in vivo as well as in vitro) to, or preventing the activation of complement on, the treponemal surface. The evidence points to a mechanism in the fluid phase, suggesting participation of a third factor in the immobilisation process, for instance an enzyme, which can be partially inhibited by rabbit serum component(s).

Animals↗
PubMed1992

A small yaws survey on the island of Sumatra, Indonesia.

Yaws (framboesia tropica), caused by Treponema pallidum subspecies pertenue, is a chronic infectious disease, found in tropical rural regions. As a result of mass treatment campaigns conducted in the 1950s and 1960s the prevalence of yaws and the other endemic treponematoses (pinta and endemic syphilis) has decreased greatly. However, in several tropical regions in the world resurgence of yaws was reported in the 1980s. In this article we present the results of a small survey on yaws in six health centres in the Pariaman region in West Sumatra, Indonesia. A general conclusion from this small survey is that yaws is far from being eradicated and that in this region the disease is on the increase again. Some major findings of T. pertenue research are presented here.

Adolescent↗
PubMed1991

Yaws in West Sumatra, Indonesia: clinical manifestations, serological findings and characterisation of new Treponema isolates by DNA probes.

The results of a yaws survey on the island of Sumatra in Indonesia are presented. The prevalence of yaws in the investigated region was found to be very high, a minimum of 300 cases per 100,000 individuals, which indicates that yaws is far from being eradicated and that campaigns for treatment are necessary. Patients suffering from early infectious yaws showed florid skin lesions. Of 101 serum samples from such patients, 100 had a positive reaction in one or more treponemal tests. The Treponema pallidum haemagglutination assay was found to be the most sensitive test (97% positive) in detecting antibodies against Treponema pallidum subsp. pertenue, followed by the fluorescent treponemal antibody absorption test (94%), the Venereal Disease Research Laboratory test and the TmpA enzyme immunoassay (91%), and analysis by Western blot using Treponema pallidum antigens (88%). Of 42 asymptomatic contacts of yaws patients 32 showed positive reactions in one or more tests, indicating that many people in the investigated region have been infected with treponemes. Eight new Treponema pallidum subsp. pertenue strains were isolated from yaws skin lesions. In vitro amplification of treponemal DNA and hybridisation with specific DNA probes showed that all eight strains were identical with Treponema pallidum subsp. pertenue CDC 2575, with regard to the subsp. pertenue specific tyfl gene.

Adolescent↗
PubMed1991

Ultrastructural aspects of infection with Treponema pallidum subspecies pertenue (Pariaman strain).

OBJECTIVE: To study ultrastructural aspects of infection with Treponema pertenue (Pariaman strain), originating from West Sumatra, Indonesia. MATERIALS AND METHODS: Biopsy material originating from skin lesions in ten young children suffering from early infectious yaws in Indonesia, and rabbit testicular tissue inoculated with T pertenue. Human skin as well as rabbit testicular tissue was examined by means of conventional electron microscopy. RESULTS: In human skin, treponemes were found in interepidermal spaces in 5 out of 10 specimens. In two of five positive specimens, treponemes were also seen in the dermis. In one out of five specimens from rabbit testicular tissue a profusion of treponemes was found lying in the interstitial myxomatous tissue. Microorganisms showed no adhesion to fibroblasts. CONCLUSION: This ultrastructural study of T pertenue demonstrated the scarcity and focal distribution of treponemes in tissue and did not reveal any morphological differences from the Gauthier strain of T pertenue. No differences from the ultrastructure of T pallidum were observed either.

Animals↗