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SEROLOGICAL SCREENING FOR ECHINOCOCCUS MULTILOCULARIS INFECTIONS WITH ELISA
1097 PENTAVALENT ANTIMONIAL TREATMENT IN MUCOSAL LEISHMANIASIS
SIR,-Most patients with mucosal leishmaniasis are infected with Leishmania braziliensis braziliensis (Lbb). Taxonomic studies of
parasite stocks from 20 ofour patients with mucosal disease showed that 19 were infected with this parasite. The treatment of the mucosal metastasis caused by Lbb is more difficult than that of the
primary skin lesion.2,3 In an analysis of 115 treatment schedules of inpatients with mucocutaneous leishmaniasis one of us (R. N. R. S.) found that only 5 of44 with cutaneous disease failed to achieve clinical cure, whereas of 71 schedules in patients with mucosal disease 24 failed (p<0 01, X2= 7. 23). The results for mucosal disease are shown in the table, for five different schedules. Amphotericin B was used in only 8 patients, with good results, although all had side-effects and 40% had a rise in blood urea and/or creatinine (schedule E). Schedule C, the association of meglumine antimonate (’Glucantime’) with nifurtimox (’Lampit’), was suggested by our previous work4in an attempt to reduce the time of hospital stay. Unfortunately, a rise in transaminases and alkaline phosphatase suggesting hepatocellular damage (both drugs are hepatotoxic) caused us to abandon this scheme after treating only 7 cases. The cure rate was unsatisfactory. Interest really centres on a comparison of schedules A, B, and D. Of the 19 failures in this group in only 2 was the lesion judged to be clinically healed and relapse occurred during follow-up. 20 symptomatic treatment effects were recorded, the five commonest being arthralgia, myalgia, loss of appetite, nausea, and vomiting, in that order. Biochemical treatment effects were usually a rise in hepatic enzyme levels (transaminases or alkaline phosphatase). In only 2 patients was the blood urea abnormal. The tubular defect of the kidney we reported after high dose antimony treatmentis rapidly corrected on cessation of the drug.6 Electrocardiographic abnormalities were repolarisation disturbances, sinus bradycardia, or T wave alterations. A statistical comparison of cure rates would not be valid because of differences in follow-up periods, and for this reason the study is continuing. Also the numbers are small. However, analysis of 13 patients in group A with a five month mean follow-up showed that 5 did not respond (62% cure), strengthening our view that B is the best schedule. A previous hospital trial showed that treatment failure during long-term follow-up was unacceptably high for schedule A,7 despite the fact that the daily dose is near the toxic single dose of 30 mg Sbv/kg. Studies in Kenya in kala-azar 8- 10 have significantly contributed to our thinking about how to use pentavalent antimonials more efficiently. They showed that the rest periods at doses of 10 or 20 mg Sbv per kg per day were unnecessary because of the rapid urinary excretion of the drug. We have tested two schedules (B and D) using this concept. Pentostam at 10 mg Sbv/kg was used in schedule D and pentostam or glucantime at 20 mg Sbv/kg in schedule B. The response to schedule B is encouraging although symptomatic side-effects were frequent (see table). is the Another aspect, recently emphasised in a WHO need to tailor treatment to the individual patient. Although patients in schedule B were treated for a mean of 30 days we had a satisfactory response with as little as 14 days in one patient (followup 7 months) while another required 85 days of this therapy to
report,
COMPARISON OF FIVE TREATMENT SCHEDULES* IN MUCOSAL LEISHMANIASIS
’Daily doses (as Sbv) were: (A) 28 mg/kg for 10-12 days repeated three times with intervals of 15 days, (B) 20 mg/kg for a mean of 30 days; (C) 28 mg/kg for 15 days (plus oral nifurtimox 10 mg/kg daily for 30 days), (D) 10 mg/kg for 30 days. Schedule (E) was amphotencm B (mean total dose 2’ 3 g).
achieve cure (follow-up 2 years), having relapsed after amphotericin B (2 - 5 g total dose). Why report such incomplete results? In Brasilia we recently calculated that the treatment of a patient with mucosal leishmaniasis, excluding salaries, laboratory support, and drugs. Such patients can be found in many hospitals in South America. Judicious use of schedule B will, we believe, reduce the costs of hospital care for many patients. However, there still exist patients who will not respond even to these antimony schedules and will require amphotericin B. Hospital Presidente Medici and Nucleo de Medicina Tropical, University of Brasilia, Brasilia DF, Brasil
R. N. R. SAMPAIO
J. H. D. SAMPAIO P. D. MARSDEN
1. Cuba CC, Marsden PD, Barreto AC, et al. Identification of human stocks of Leishmania spp isolated from patients with mucocutaneous leishmaniasis m Três Braços, Bahia-Brazil. Trans Roy Soc Trop Med Hyg 1984, 78: 708-10. 2. Llanos-Cuentas EA, Marsden PD, Lago EL, et al. Human mucocutaneous leishmaniasis in Três Braços, Bahia-Brazil. An area of Leishmania braziliensis braziliensis transmission II: Cutaneous disease presentation and evolution. Rev Soc Bras Med Trop 1984; 17: 169-77. 3 Marsden PD, Llanos-Cuentas EA, Lago EL, et al. Human mucocutaneous leishmaniasis in Três Braços, Bahia-Brazil. An area of Leishmama braziliensis braziliensis transmission III: Mucosal disease presentation and initial evolution. Rev Soc Bras Med Trop 1984; 17: 179-86. 4. Guerra M, Marsden PD, Cuba CC, Barreto AC. Further studies of nifurtimox in the treatment of mucocutaneous leishmaniasis. Trans Roy Soc Trop Med Hyg 1981; 75: 335-37. 5.
Veiga JPR, Wolff ER, Sampaio RN, Marsden PD. Renal tubular dysfunction
in
patients with mucocutaneous leishmaniasis treated with pentavalent leishmaniasis. Lancet 1983, ii: 569. 6 Veiga JPR, Rosa TT, Kimachi T, et al. renal em pacientes com leishmaniose mucocutânea tratados com antimoniais pentavalentes. Rev Inst Med Trop São Paulo
Função
(in press). Sampaio RNR,
Rocha RAA, Marsden PD, Cuba CC, Barreto AC. Leishmaniose tegumentar americana: Casuistica do Hospital Escola da UnB. Anais Brasil Dermatol 1980, 55: 69-76. 8. Anabwani GM, Nigra JA, Dimiti G, Bryceson ADM. Comparison of two dosage schedules of sodium stibogluconate in the treatment of visceral leishmaniasis in Kenya. Lancet 1983; i: 210-13. 9. Chulay JD, Bhatt SM, Mulgai R, et al. A comparison of three dosage regimens of sodium stibogluconate in the treatment of visceral leishmaniasis in Kenya. I Infect Dis 1983; 148: 148-55. 10. Chulay JD, Anzeze EM, Kohch DK, Bryceson ADM. High dose sodium subogluconate treatment of cutaneous leishmaniasis in Kenya. Trans Roy Soc Trop Med Hyg 1983; 77: 717-21. 11. WHO. The leishmaniases. WHO Tech Rep Ser 1984; no 701. 7.
SEROLOGICAL SCREENING FOR ECHINOCOCCUS MULTILOCULARIS INFECTIONS WITH ELISA
SIR,-Alveolar hydatid disease, caused by the larval stage of Echinococcus multilocularis, is one of the most lethal helminthic infections of man. The insidious and progressive nature of the disease usually results in delayed onset of symptoms and diagnosis, by which time the lesions have invaded extensively or metastasised and are usually inoperable. The proportion of surgically resectable 1-4 Of the non-resectable cases, 90% of cases varies from 20% to 40%. 10 died within patients years.3Data reported by Kasai and others from Japan suggest that cases diagnosed in the early preclinical stages of disease were likely to be surgically resectable and, consequently, cured of the disease.4 In contrast, all patients diagnosed in the advanced, non-resectable stage of disease died. Serological screening for early diagnosis of alveolar hydatid disease has been offered to communities in endemic areas of Alaska for many years, and 8 of 33 cases diagnosed before 1980 were first detected serologically. Screening tests have included indirect haemagglutination (IHA) and arc-5 double diffusion (DD5) with antigens prepared from E granulosus hydatid fluid. E granulosus antigens are more readily available than antigens from homologous E multilocularis; the two species share antigens; and antigens prepared from Egranulosus are highly reactive with sera of patients with E multilocularis infections.6 Clinical experience in Alaska indicated that 94% of patients’ sera had antibody reactive with Egranulosus antigens.We have lately observed, however, that sera of some patients with alveolar hydatid disease do not react with E granulosus antigens but do react with a purified species-specific antigen of E multilocularis.
1098 In 1983 and 1984, sera from 1103 people living in endemic areas in Alaska were screened by IHA with E granulosus antigens, and those with titres of 64 or more were tested for the echinococcal arc-5 by DD5. People positive for arc-5 or with an IHA titre of 512 or more were examined for clinical evidence of alveolar hydatid disease. Active disease was diagnosed in 2 persons who were arc-5 positive and 2 persons who were arc-5 negative but had IHA titres of 512 or more. Subsequently, all sera were tested by the enzymelinked immunosorbent assay (ELISA) with a purified E multilocularis antigen.8,9 Sera of 35 persons were positive in this test. These included all 4 previously identified patients and 31 others whose sera had not been reactive in tests with E granulosus antigens. So far 3 of these 31 have been examined clinically and radiographically. None has clinical disease, but all had liver lesions with radiological features typical of alveolar hydatid diseaselO on
SPECIFIC RECOGNITION OF DEFINED POLYPEPTIDE BANDS IN RELATION TO GESTATION AND PARASITAEMIA
computerised tomography. E multilocularis infection is enzootic in foxes and a variety of rodent intermediate hosts over a broad area of North America and Eurasia. Human alveolar hydatid disease is reported regularly from endemic regions in central Europe, Siberia, the Japanese island of 5 Hokkaido, and Alaska. Serologic screening for early detection of cases may reduce morbidity and mortality by increasing the proportion of cases1 that may be surgically resectableor responsive to
chemotherapy.
Institute of Parasitology, Zurich, Switzerland
B. GOTTSTEIN
Center for Infectious Diseases, Centers for Disease Control, Atlanta, Georgia 30333, USA
P. M. SCHANTZ
Alaska Native Medical Center,
J. F. WILSON
Anchorage, Alaska 1. Wilson
JF, Rausch RL. Alveolar hydatid disease: a review of clinical features of 33 indigeneous cases of Echinococcus multilocularis infection in Alaskan Esimos. AmJ Trop Med Hyg 1980; 24: 1340-55. 2. Semenov VS, Pechen OR, Poporodu P. Alveolianogo ekkinokokko. Vestnik Khirurgia Grekov 1954; 74: 20. 3. Mosimann F. Is alveolar hydatid disease of the liver incurable? Ann Surg 1980; 192: 118-23. 4. Kasai Y, Koshmo I, Kawanishi N, Sakamoto H, Sasaki E, Kumagai M. Alveolar echinococcosis of the liver. Ann Surg 1980; 191: 145-52. 5. Schantz PM. Echinococcosis. In: Arambulo P, Jacobs L, eds. CRC handbook series of zoonoses, section C: Parasitic zoonoses, vol I. Boca Raton, Florida: CRC Press, 1982: 231-77. 6. Norman L, Kagan IG, Allain DS. Preparation and evaluation of antigens for use in the serologic diagnosis of human hydatid disease II: Isolation and characterization from extracts of Echinococcus multilocularis of serologically reactive elements found in 1966; 96: 822-29. hydatid fluid of E granulosus. Immunol J 7. Schantz PM, Wilson JF, Wahlquist SP, Boss LP, Rausch RL. Serologic tests for diagnosis and posttreatment evaluation of patients with alveolar hydatid disease
women had attended for their first antenatal visit early in gestation (mean gestational age 15 weeks) and the others late in gestation (mean 31 weeks). An equal number of sera with positive or negative malaria blood smears was selected for both these gestational age-groups. A strain of P falciparum (M25) isolated from a Zairean patient was used for in-vitro culture.2 Metabolic labelling of Pfalciparum asexual stages and immunoprecipitation and SDS PAGE were done as described previously.3 Dilutions containing 7, 1’ 5,0’ 7, and 0’ 015 µl of undiluted serum in a final volume of70 JAI
of the
tested. With autoradiography the sera often recognised more than 20 distinct polypeptide bands with molecular weights ranging from less than 30 kD to more than 200 kD (see accompanying figure and table). The distribution of the pattern of recognition between sera was not uniform. More polypeptide bands were recognised by late-pregnancy sera. This difference is more apparent for polypeptide bands recognised with high dilution sera (0’ 015 µl of undiluted sera incubated with extract containing 5 x 106 parasites), and for women without parasitaemia. It is most pronounced at either high or low serum dilution (7 pl of undiluted sera) for the 140 kD polypeptide. This study was not longitudinal, so we do not know whether these findings indicate that women in late pregnancy have developed immunity to specific antigenic types during pregnancy. An excess of schizonts is present in placental intervillous spaces late in pregnancy,4-6 which could be a stimulus for production of schizontspecific antibody. Early in pregnancy the placenta provides no facilities for the post-ring development of P falciparasm. were
of polypeptides
(Echinococcus multilocularis). Am J Trop Med Hyg 1983, 32: 1381-86. 8. Gottstein B, Eckert J, Fey H. Serological differentiation between Echinococcus granulosus and E multilocularis infections in man. Z Parasitenkd 1983; 69: 347-56. 9. Gottstein B. Purification and characterization of a specific antigen from Echinococcus multilocularis. Parasite Immunol (in press). 10. Lasseque A, Deschamps J-P, Vuitton D, et al. Apport de la tomodensitometrie au diagnostic et a la surveillance de l’echinococcose alveolaire hepatique. Gastroenterol Clin Biol 1982; 6: 901-09.
DIVERSITY OF PLASMODIUM FALCIPARUM ANTIBODIES IN PREGNANCY
SIR,—Dr Deloron
al (Feb 23, p 444) have concluded that the immunological response to Plasmodium falciparum among symptomless patients with parasitaemia may vary with degree of malaria endemicity. They consider several possible mechanisms that could explain the variable distribution of plasmodial polypeptides recognised by patient sera from different regions (population differences in antibody response, antigenic diversity of malarial strains, selection processes influencing expression of proteins). In adult women, this variation may also result from pregnancy-associated changes in maternal immunity. We have recently observed, by the use of immunoprecipitation and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE), that late-pregnancy sera show enhanced recognition of schizont-specific polypeptides of P falciparum. 40 pregnancy sera from symptomless women living under holoendemic conditions and attending a rural antenatal clinic in West Kenya were tested.]Some et
with SDS PAGE showing the immunoprecipitates obtained with sera from 4 multigravidae without parasitaemia taken late in pregnancy, at two dilutions: 7 III (a) and 1.5µl (b).
Autoradiography
Column 5 represents the 35S-methionine extract-starting material. Arrows indicate the pclypeptides of 200, 160, 140, 105, 82, and 41 kD. Molecular weights (Pharmacia) are indicated.
SIR,-Most patients with mucosal leishmaniasis are infected with Leishmania braziliensis braziliensis (Lbb). Taxonomic studies of
parasite stocks from 20 ofour patients with mucosal disease showed that 19 were infected with this parasite. The treatment of the mucosal metastasis caused by Lbb is more difficult than that of the
primary skin lesion.2,3 In an analysis of 115 treatment schedules of inpatients with mucocutaneous leishmaniasis one of us (R. N. R. S.) found that only 5 of44 with cutaneous disease failed to achieve clinical cure, whereas of 71 schedules in patients with mucosal disease 24 failed (p<0 01, X2= 7. 23). The results for mucosal disease are shown in the table, for five different schedules. Amphotericin B was used in only 8 patients, with good results, although all had side-effects and 40% had a rise in blood urea and/or creatinine (schedule E). Schedule C, the association of meglumine antimonate (’Glucantime’) with nifurtimox (’Lampit’), was suggested by our previous work4in an attempt to reduce the time of hospital stay. Unfortunately, a rise in transaminases and alkaline phosphatase suggesting hepatocellular damage (both drugs are hepatotoxic) caused us to abandon this scheme after treating only 7 cases. The cure rate was unsatisfactory. Interest really centres on a comparison of schedules A, B, and D. Of the 19 failures in this group in only 2 was the lesion judged to be clinically healed and relapse occurred during follow-up. 20 symptomatic treatment effects were recorded, the five commonest being arthralgia, myalgia, loss of appetite, nausea, and vomiting, in that order. Biochemical treatment effects were usually a rise in hepatic enzyme levels (transaminases or alkaline phosphatase). In only 2 patients was the blood urea abnormal. The tubular defect of the kidney we reported after high dose antimony treatmentis rapidly corrected on cessation of the drug.6 Electrocardiographic abnormalities were repolarisation disturbances, sinus bradycardia, or T wave alterations. A statistical comparison of cure rates would not be valid because of differences in follow-up periods, and for this reason the study is continuing. Also the numbers are small. However, analysis of 13 patients in group A with a five month mean follow-up showed that 5 did not respond (62% cure), strengthening our view that B is the best schedule. A previous hospital trial showed that treatment failure during long-term follow-up was unacceptably high for schedule A,7 despite the fact that the daily dose is near the toxic single dose of 30 mg Sbv/kg. Studies in Kenya in kala-azar 8- 10 have significantly contributed to our thinking about how to use pentavalent antimonials more efficiently. They showed that the rest periods at doses of 10 or 20 mg Sbv per kg per day were unnecessary because of the rapid urinary excretion of the drug. We have tested two schedules (B and D) using this concept. Pentostam at 10 mg Sbv/kg was used in schedule D and pentostam or glucantime at 20 mg Sbv/kg in schedule B. The response to schedule B is encouraging although symptomatic side-effects were frequent (see table). is the Another aspect, recently emphasised in a WHO need to tailor treatment to the individual patient. Although patients in schedule B were treated for a mean of 30 days we had a satisfactory response with as little as 14 days in one patient (followup 7 months) while another required 85 days of this therapy to
report,
COMPARISON OF FIVE TREATMENT SCHEDULES* IN MUCOSAL LEISHMANIASIS
’Daily doses (as Sbv) were: (A) 28 mg/kg for 10-12 days repeated three times with intervals of 15 days, (B) 20 mg/kg for a mean of 30 days; (C) 28 mg/kg for 15 days (plus oral nifurtimox 10 mg/kg daily for 30 days), (D) 10 mg/kg for 30 days. Schedule (E) was amphotencm B (mean total dose 2’ 3 g).
achieve cure (follow-up 2 years), having relapsed after amphotericin B (2 - 5 g total dose). Why report such incomplete results? In Brasilia we recently calculated that the treatment of a patient with mucosal leishmaniasis, excluding salaries, laboratory support, and drugs. Such patients can be found in many hospitals in South America. Judicious use of schedule B will, we believe, reduce the costs of hospital care for many patients. However, there still exist patients who will not respond even to these antimony schedules and will require amphotericin B. Hospital Presidente Medici and Nucleo de Medicina Tropical, University of Brasilia, Brasilia DF, Brasil
R. N. R. SAMPAIO
J. H. D. SAMPAIO P. D. MARSDEN
1. Cuba CC, Marsden PD, Barreto AC, et al. Identification of human stocks of Leishmania spp isolated from patients with mucocutaneous leishmaniasis m Três Braços, Bahia-Brazil. Trans Roy Soc Trop Med Hyg 1984, 78: 708-10. 2. Llanos-Cuentas EA, Marsden PD, Lago EL, et al. Human mucocutaneous leishmaniasis in Três Braços, Bahia-Brazil. An area of Leishmania braziliensis braziliensis transmission II: Cutaneous disease presentation and evolution. Rev Soc Bras Med Trop 1984; 17: 169-77. 3 Marsden PD, Llanos-Cuentas EA, Lago EL, et al. Human mucocutaneous leishmaniasis in Três Braços, Bahia-Brazil. An area of Leishmama braziliensis braziliensis transmission III: Mucosal disease presentation and initial evolution. Rev Soc Bras Med Trop 1984; 17: 179-86. 4. Guerra M, Marsden PD, Cuba CC, Barreto AC. Further studies of nifurtimox in the treatment of mucocutaneous leishmaniasis. Trans Roy Soc Trop Med Hyg 1981; 75: 335-37. 5.
Veiga JPR, Wolff ER, Sampaio RN, Marsden PD. Renal tubular dysfunction
in
patients with mucocutaneous leishmaniasis treated with pentavalent leishmaniasis. Lancet 1983, ii: 569. 6 Veiga JPR, Rosa TT, Kimachi T, et al. renal em pacientes com leishmaniose mucocutânea tratados com antimoniais pentavalentes. Rev Inst Med Trop São Paulo
Função
(in press). Sampaio RNR,
Rocha RAA, Marsden PD, Cuba CC, Barreto AC. Leishmaniose tegumentar americana: Casuistica do Hospital Escola da UnB. Anais Brasil Dermatol 1980, 55: 69-76. 8. Anabwani GM, Nigra JA, Dimiti G, Bryceson ADM. Comparison of two dosage schedules of sodium stibogluconate in the treatment of visceral leishmaniasis in Kenya. Lancet 1983; i: 210-13. 9. Chulay JD, Bhatt SM, Mulgai R, et al. A comparison of three dosage regimens of sodium stibogluconate in the treatment of visceral leishmaniasis in Kenya. I Infect Dis 1983; 148: 148-55. 10. Chulay JD, Anzeze EM, Kohch DK, Bryceson ADM. High dose sodium subogluconate treatment of cutaneous leishmaniasis in Kenya. Trans Roy Soc Trop Med Hyg 1983; 77: 717-21. 11. WHO. The leishmaniases. WHO Tech Rep Ser 1984; no 701. 7.
SEROLOGICAL SCREENING FOR ECHINOCOCCUS MULTILOCULARIS INFECTIONS WITH ELISA
SIR,-Alveolar hydatid disease, caused by the larval stage of Echinococcus multilocularis, is one of the most lethal helminthic infections of man. The insidious and progressive nature of the disease usually results in delayed onset of symptoms and diagnosis, by which time the lesions have invaded extensively or metastasised and are usually inoperable. The proportion of surgically resectable 1-4 Of the non-resectable cases, 90% of cases varies from 20% to 40%. 10 died within patients years.3Data reported by Kasai and others from Japan suggest that cases diagnosed in the early preclinical stages of disease were likely to be surgically resectable and, consequently, cured of the disease.4 In contrast, all patients diagnosed in the advanced, non-resectable stage of disease died. Serological screening for early diagnosis of alveolar hydatid disease has been offered to communities in endemic areas of Alaska for many years, and 8 of 33 cases diagnosed before 1980 were first detected serologically. Screening tests have included indirect haemagglutination (IHA) and arc-5 double diffusion (DD5) with antigens prepared from E granulosus hydatid fluid. E granulosus antigens are more readily available than antigens from homologous E multilocularis; the two species share antigens; and antigens prepared from Egranulosus are highly reactive with sera of patients with E multilocularis infections.6 Clinical experience in Alaska indicated that 94% of patients’ sera had antibody reactive with Egranulosus antigens.We have lately observed, however, that sera of some patients with alveolar hydatid disease do not react with E granulosus antigens but do react with a purified species-specific antigen of E multilocularis.
1098 In 1983 and 1984, sera from 1103 people living in endemic areas in Alaska were screened by IHA with E granulosus antigens, and those with titres of 64 or more were tested for the echinococcal arc-5 by DD5. People positive for arc-5 or with an IHA titre of 512 or more were examined for clinical evidence of alveolar hydatid disease. Active disease was diagnosed in 2 persons who were arc-5 positive and 2 persons who were arc-5 negative but had IHA titres of 512 or more. Subsequently, all sera were tested by the enzymelinked immunosorbent assay (ELISA) with a purified E multilocularis antigen.8,9 Sera of 35 persons were positive in this test. These included all 4 previously identified patients and 31 others whose sera had not been reactive in tests with E granulosus antigens. So far 3 of these 31 have been examined clinically and radiographically. None has clinical disease, but all had liver lesions with radiological features typical of alveolar hydatid diseaselO on
SPECIFIC RECOGNITION OF DEFINED POLYPEPTIDE BANDS IN RELATION TO GESTATION AND PARASITAEMIA
computerised tomography. E multilocularis infection is enzootic in foxes and a variety of rodent intermediate hosts over a broad area of North America and Eurasia. Human alveolar hydatid disease is reported regularly from endemic regions in central Europe, Siberia, the Japanese island of 5 Hokkaido, and Alaska. Serologic screening for early detection of cases may reduce morbidity and mortality by increasing the proportion of cases1 that may be surgically resectableor responsive to
chemotherapy.
Institute of Parasitology, Zurich, Switzerland
B. GOTTSTEIN
Center for Infectious Diseases, Centers for Disease Control, Atlanta, Georgia 30333, USA
P. M. SCHANTZ
Alaska Native Medical Center,
J. F. WILSON
Anchorage, Alaska 1. Wilson
JF, Rausch RL. Alveolar hydatid disease: a review of clinical features of 33 indigeneous cases of Echinococcus multilocularis infection in Alaskan Esimos. AmJ Trop Med Hyg 1980; 24: 1340-55. 2. Semenov VS, Pechen OR, Poporodu P. Alveolianogo ekkinokokko. Vestnik Khirurgia Grekov 1954; 74: 20. 3. Mosimann F. Is alveolar hydatid disease of the liver incurable? Ann Surg 1980; 192: 118-23. 4. Kasai Y, Koshmo I, Kawanishi N, Sakamoto H, Sasaki E, Kumagai M. Alveolar echinococcosis of the liver. Ann Surg 1980; 191: 145-52. 5. Schantz PM. Echinococcosis. In: Arambulo P, Jacobs L, eds. CRC handbook series of zoonoses, section C: Parasitic zoonoses, vol I. Boca Raton, Florida: CRC Press, 1982: 231-77. 6. Norman L, Kagan IG, Allain DS. Preparation and evaluation of antigens for use in the serologic diagnosis of human hydatid disease II: Isolation and characterization from extracts of Echinococcus multilocularis of serologically reactive elements found in 1966; 96: 822-29. hydatid fluid of E granulosus. Immunol J 7. Schantz PM, Wilson JF, Wahlquist SP, Boss LP, Rausch RL. Serologic tests for diagnosis and posttreatment evaluation of patients with alveolar hydatid disease
women had attended for their first antenatal visit early in gestation (mean gestational age 15 weeks) and the others late in gestation (mean 31 weeks). An equal number of sera with positive or negative malaria blood smears was selected for both these gestational age-groups. A strain of P falciparum (M25) isolated from a Zairean patient was used for in-vitro culture.2 Metabolic labelling of Pfalciparum asexual stages and immunoprecipitation and SDS PAGE were done as described previously.3 Dilutions containing 7, 1’ 5,0’ 7, and 0’ 015 µl of undiluted serum in a final volume of70 JAI
of the
tested. With autoradiography the sera often recognised more than 20 distinct polypeptide bands with molecular weights ranging from less than 30 kD to more than 200 kD (see accompanying figure and table). The distribution of the pattern of recognition between sera was not uniform. More polypeptide bands were recognised by late-pregnancy sera. This difference is more apparent for polypeptide bands recognised with high dilution sera (0’ 015 µl of undiluted sera incubated with extract containing 5 x 106 parasites), and for women without parasitaemia. It is most pronounced at either high or low serum dilution (7 pl of undiluted sera) for the 140 kD polypeptide. This study was not longitudinal, so we do not know whether these findings indicate that women in late pregnancy have developed immunity to specific antigenic types during pregnancy. An excess of schizonts is present in placental intervillous spaces late in pregnancy,4-6 which could be a stimulus for production of schizontspecific antibody. Early in pregnancy the placenta provides no facilities for the post-ring development of P falciparasm. were
of polypeptides
(Echinococcus multilocularis). Am J Trop Med Hyg 1983, 32: 1381-86. 8. Gottstein B, Eckert J, Fey H. Serological differentiation between Echinococcus granulosus and E multilocularis infections in man. Z Parasitenkd 1983; 69: 347-56. 9. Gottstein B. Purification and characterization of a specific antigen from Echinococcus multilocularis. Parasite Immunol (in press). 10. Lasseque A, Deschamps J-P, Vuitton D, et al. Apport de la tomodensitometrie au diagnostic et a la surveillance de l’echinococcose alveolaire hepatique. Gastroenterol Clin Biol 1982; 6: 901-09.
DIVERSITY OF PLASMODIUM FALCIPARUM ANTIBODIES IN PREGNANCY
SIR,—Dr Deloron
al (Feb 23, p 444) have concluded that the immunological response to Plasmodium falciparum among symptomless patients with parasitaemia may vary with degree of malaria endemicity. They consider several possible mechanisms that could explain the variable distribution of plasmodial polypeptides recognised by patient sera from different regions (population differences in antibody response, antigenic diversity of malarial strains, selection processes influencing expression of proteins). In adult women, this variation may also result from pregnancy-associated changes in maternal immunity. We have recently observed, by the use of immunoprecipitation and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE), that late-pregnancy sera show enhanced recognition of schizont-specific polypeptides of P falciparum. 40 pregnancy sera from symptomless women living under holoendemic conditions and attending a rural antenatal clinic in West Kenya were tested.]Some et
with SDS PAGE showing the immunoprecipitates obtained with sera from 4 multigravidae without parasitaemia taken late in pregnancy, at two dilutions: 7 III (a) and 1.5µl (b).
Autoradiography
Column 5 represents the 35S-methionine extract-starting material. Arrows indicate the pclypeptides of 200, 160, 140, 105, 82, and 41 kD. Molecular weights (Pharmacia) are indicated.