- Email: [email protected]
RENAL INSUFFICIENCY WITH NEBULISED PENTAMIDINE
1045 the
possibility
of a chemical interaction
resulting in
a
colourless,
soluble and undesirable byproduct is not excluded.
compatibility used to be made for antiemetic and mixtures 34but several interactions were uncovered.5 diamorphine Cyclizine and diamorphine mixtures proved to be liable to precipitate or crystallise if the concentration of either drug was above 25 mg/ml, although the concentration of the second drug was below 10 mg/ml. The compatibility studies also uncovered a risk of Claims of
metoclopramide degradation if this was mixed with diamorphine, precipitation in a haloperidol and diamorphine
and the risk of
mixture with a loss of 58% of the haloperidol from solution. The enthusiasm for mixing drugs together in subcutaneous infusions should be tempered until further compatibility studies can be completed. St Oswald’s Hospice,
CLAUD F. B. REGNARD KATHRYN MANNIX
Gosforth, Newcastle upon Tyne NE3 1EE
1. de Sousa E, Jepson BA. Midazolam in terminal care. Lancet 1988; i: 67-68. 2. Martindale: the extra pharmacopoeia. 28th ed. London: Pharmaceutical Press, 1982: 801. 3. Hutchinson HT, Leedham GD, Knight AM. Continuous subcutaneous analgesics and antiemetics in domiciliary terminal care. Lancet 1981; ii: 1279. 4. Oliver DJ. The use of the syringe driver in terminal care. Br J Clin Pharmacol 1985; 20: 515-16.
5.
Regnard C, Pashley S, Westrope F. Antiemetic/diamorphine mixture compatibility in infusion pumps. BrJ Pharm Pract 1986; 8: 218-20.
CONTINUOUS CLEARANCE OF HIV IN A VERTICALLY INFECTED CHILD
SiR,—The proportion of children infected prenatally with HIV who lose their antibodies but remain HIV carriers is unknown. We report virological and clinical data on a healthy 18-month-old congenitally HIV-infected child. The female baby was born in December, 1987, of an HIVinfected drug-addict mother and HIV-negative father. The mother is symptom-free. Absolute lymphocyte count, lymphocyte subsets, monocytes, and platelet count were normal at birth and on five occasions up to May, 1989. The child was not breast-fed or vaccinated. The T 4/T ratio increased from 1-46 at birth to 2.76 in May, 1989. At birth the HIV-antibody pattern of the mother and child was identical. Subsequent tests showed a continuous decrease of serum antibody concentrations in the child: only weak positive tests were obtained by ELISA and western-blotting by seven months after birth, and the indirect immunofluorescence test was negative at that time. Viral p24 antigen in plasma was never detected. A high number of unstimulated cord blood lymphocytes screened for viral antigen expression tested positive (anti-p24, 7/68; anti-pl7, 2/300, anti-gpl20, 5/57). At 18 months no positive cells could be identified in PBMC (peripheral blood mononuclear cells) by any of the three monoclonal antibodies used. In virus culture cord-blood lymphocytes showed a strong cytopathic effect with typical syncytia formation 3 days after co-cultivation. At this time p24 antigen became detectable in culture supernatant, reaching a peak at about 10 days, whereas at 12 months the cytopathic effect occurred later and p24-antigen concentrations were much lower
than at birth (figure). On both occasions viral DNA in PBMC was detected by PCR (polymerase chain reaction). The virus was a high-replicating, syncytia inducing type at birth, and could be easily transfected onto a permanent T-cell line (Sup T1). At 12 months the virus was slow replicating and could not be propagated on Sup Tl. In April and May, 1989, virus cultures and PCRs were negative. The mother’s lymphocytes were negative for HIV at the time of delivery. The disappearance of HIV in a congenitally infected child is notable. The striking cytopathic effect in the first virus isolation with cord blood seen after only three days could be the result of a high number of infected cells rather than a rapidly replicating virus type. The underlying mechanisms for the disappearance of HIV might be explained as immunological tolerance or as an impaired specific immune response to HIV, in that cytotoxic T lymphocytes (CTLs) and/or antibody production might be suppressed.1 The possible absence of a specific immune response could have been a major advantage for the host since CD depletion may be caused by CTLs and/or antibody-dependent cellular cytotoxicity.2 The rise in the T4/Tg ratio may be indirect evidence for this. The shift from a low-replicating, non-syncytia-inducing to a high-replicating-syncytia-inducing virus type, is commonly seen in individuals proceeding to the final stages of AIDS.3,4 The reverse fmding in our patient could be the result of a continuous clearing of HIV subtypes. High-replicating virus types may be eliminated more efficiently than low-replicating subtypes, which are less expressed on the infected cell surface and therefore may be detected and eliminated at a slow rate.5 Alternatively, there may be a shift in the cell reservoir of the virus.6 An initially high-replicating mainly lymphotropic virus could have been depleted by the immune defence and a low-replicating more monocytotropic subtype selected. Therefore the clearing of HIV from the peripheral blood could indicate another stage of the incubation period. It remains to be seen whether the infection status in this child reflects viral latency or silent viral persistence. One possibility to be considered is that the virus load is cleared entirely in some cases and that the once infected children become HIV negative.
Institute for Clinical and Molecular Medicine Clinic III, and Children’s and Polyclinics, University of Erlangen-Nurnberg, 8520 Erlangen, West Germany
Virology,
ANDREAS BAUR NORBERT SCHWARZ SYLVIA ELLINGER KLAUS KORN THOMAS HARRER KARLA MANG
GERHARD JAHN
Jamieson BD, Ahmed R. T-cell tolerance: exposure to virus in utero does not cause a permanent deletion of specific T-cells. Proc Natl Acad Sci USA 1988; 85: 2265-68. 2. Germain RN. Antigen processing and CD4 T-cell depletion in AIDS. Cell 1988; 54: 1.
441-44. 3. Tersmette M, Gruters
R, De Wolf F,
et
al. Evidence for
a
role of virulent human
immunodeficiency virus (HIV) variants in the pathogenesis of acquired immunodeficiency syndrome: studies on sequential HIV isolates. J Virol 1989; 63: 2118-25. 4. Tersmette M,
5.
Lange JMA, de Goede REY, et al. Association between biological properties of human immunodeficiency virus variants and risk for AIDS and AIDS mortality. Lancet 1989; i: 983-85. Leonard R, Zagury D, Desportes I, et al. Cytopathic effect of human immunodeficiency virus in T4 cells is linked to the last stage of virus infection. Proc
Natl Acad Sci USA 1988; 85: 3570-74. 6. McElrath MJ, Pruett JE, Cohn ZA. Mononuclear phagocytes of blood and bone marrow: comparative roles as viral reservoirs in human immunodeficiency virus type 1 infections. Proc Natl Acad Sci USA 1989; 86: 675-79.
RENAL INSUFFICIENCY WITH NEBULISED PENTAMIDINE
SIR,-Dr Miller and colleagues (June 3, p 1273) report the first of acute renal failure associated with nebulised pentamidine. We report a patient in whom nebulised pentamidine seems to be responsible for renal insufficiency. A 59-year-old HIV-1-positive man was admitted for Pneumocystis carinii pneumonia. He was initially treated by intravenous trimethoprim (1-92 g daily) and sulfamethoxazole (9-600 g daily). This treatment was withdrawn because of severe skin reaction. Intramuscular pentamidine was begun (4 mg/g daily). Before this therapy, blood urea was 57 mmol/1 and creatinine 79 case
Days
of cultivation
T-co-cultivation with neg Concentration
of
PMBC
p24 antigen and cytopathic effect child at birth (A) and at twelve months (B).
(CPE)
in the
Arrows = time of CPE. Cells prestimulated with phytohaemagglutinin
(PHA) for 3 days before co-cultivation with negative PBMC.
1046
pmol/1. During the first week, blood urea and creatinine levels progressively increased to 7-3 mmol/1 and 123 Eunol/1, respectively, and intramuscular pentamidine was replaced by nebulised pentamidine (240 mg daily). Nonetheless, renal insufficiency progressed (urea 11-11 mmol/1; creatinine 140 umol/1) and after one more week, pentamidine was withdrawn and replaced by a progressive dose of trimethoprim/sulfamethoxazole. Urinalysis was unremarkable and no other cause of renal dysfunction was identified during nebulised pentamidine. Blood urea and creatinine levels rapidly returned to pretreatment values. Renal insufficiency is known to occur with parenteral pentamidine.1 Since in our patient renal insufficiency progressed despite the use of nebulised pentamidine, we conclude that this form is also contraindicated in such patients. Service of Internal Medicine, Hopital de la Pitié, Pans 75013, France
CATHERINE CHAPELON GILLES RAGUIN CHRISTIAN DE GENNES
1. Sattler FR, Cowan R, Neilsen DM, et al. Trimethoprim-sulfamethoxazole compared with pentamidine for treatment of Pneumocystis carinii pneumonia in the acquired immunodeficiency syndrome. Ann Intern Med 1988; 109: 280-87.
NICOTINE AND TOURETTE’S SYNDROME
SIR,-Sanberg et all reported two children with Tourette’s syndrome who responded to the addition of nicotine to standard treatment. We report striking improvement of Tourette’s symptoms in a smoker, presumably as a result of nicotine in cigarettes. A 21-year-old man with Tourette’s syndrome was first seen by us in 1988. Tourette symptoms had begun at age 8 years, with eye-blinking and a lateral head twitch. Typical progression of symptoms followed, including onset of vocal tics at age 9 years and more complex motor tics such as contractions of leg and abdominal muscles by age 10, when Tourette’s syndrome was diagnosed. Other medical problems include abnormal genitourinary tract development evidenced by bilateral ureter reimplantation at age 2 years and repair of two abdominal hernias and undescended testes at age 3. Hypospadias was also noted. The patient has a slight build (169 cm tall and 43-1kg weight) with noticeable spinal curvature and narrow shoulders. Facial dysmorphologies including low-set ears and asymmetrical jaw and orbits. Karyotyping at 550 band resolution revealed a normal 46 XY male chromosome complement. He had a history of bronchitis and asthma. Initial treatment with haloperidol was unsuccessful because of oversedation. Subsequent treatment with clonidine and pimozide were also unsuccessful, partly because of non-compliance. At age 16 the patient began to smoke cigarettes and progressed to 20 a day. Both the patient and his immediate family reported that Tourette symptoms became less severe in the absence of other medication. In January, 1989, the patient gave up smoking because of concern about respiratory problems, but symptoms of Tourette’s reappeared in a milder form than previously. We suggest that the cessation of symptoms was due to nicotine received during smoking. Reappearance of symptoms was the result of stopping smoking, which argues against spontaneous remission as an alternative explanation. Nicotine is a psychoactive drug2 with dopamine-like effects.3 The observation that Tourette’s symptoms are responsive to nicotine has implications for the aetiology and treatment of the syndrome. Nicotine might be useful in other neuroleptic responsive disorders. Department of Psychiatry, Washington University School of Medicine, St Louis, Missouri 63110, USA
1. Sanberg PR, Fogelson HM,
ERIC J. DEVOR KEITH E. ISENBERG
Manderscheid PZ, Parker KW, Norman AB, McConville BJ. Nicotine gum and haloperidol in Tourette’s syndrome. Lancet 1988; i: 592. 2. Jones RT. Tobacco dependence. In: Meltzer HY, ed. Psychopharmacology: the third generation of progress. New York: Raven Press, 1987: 1589-95. 3. Lapin EP, Maker HS, Sershen H, Hurd Y, Lajtha A. Dopamine-like action of nicotine: lack of tolerance and reverse tolerance. Brain Res 1987, 407: 351-63.
STORAGE OF CEREBROSPINAL FLUID ON PAPER
SIR,-Diagnosis of infectious diseases of the nervous system by enzyme-linked immunosorbent assay (ELISA)’ on cerebrospinal fluid (CSF) is difficult in countries that have few laboratories doing these tests. In such circumstances reference centres have had to be set up, and preservation and transportation of CSF for immunodiagnosis is costly and difficult, especially in underdeveloped countries where infectious diseases are endemic. We report the storage of CSF on ordinary paper for mailing to reference centres. 1 ml of CSF is placed on white paper measuring 4 x2 cm. The paper is then left to dry at room temperature for about 3 h, the patient’s name and code number being recorded in pencil on the paper. The paper is cut in the laboratory into eight strips of 205 cm. To test this form of storage we selected for ELISA testing 108 CSF samples from patients with neurocysticercosis (NCC) positive to cysticercus antigens, and 11 from patients with subacute sclerosing panencephalitis (SSPE) positive to measles antigens. In addition, 210 CSF samples from patients with various neurological disorders were negative controls. A 96-well microtitre plate was loaded with cysticercus antigen, and the paper strips folded in a zig-zag were placed in the wells. 200pi of phosphate-buffered saline (PBS) polysorbate 20 were added to each well and left overnight. The strips were then removed and the wells washed. 200 1 of a mixture of 1/1000 rabbit anti-human IgG plus 1/1000 rabbit anti-human IgM alkaline phosphatase conjugates diluted in PBS-polysorbate 20 were added and left for 90 minutes, the wells were washed, and colour was developed with p-nitrophenyl substrate. Results above 0-40 optical density (OD) at 420 nm were regarded as positive. All paper strips had remained at room temperature for 15 days before testing. The fresh CSF samples were also tested by ELISA, at a dilution of 1 in 30 in PBS. We also tested by ELISA fresh and stored CSF samples from SSPE patients for measles antigens. In fresh CSF samples, 108 were positive for cysticercosis by ELI SA and 210 were negative. When the test was repeated with the storage strips, 105 samples from NCC patients remained positive and all negative samples remained negative, giving 97% concordance for true positives and 100% concordance for true negatives; results obtained for measles virus in SSPE patients showed 100% and 98%
concordance, respectively. Previous studies have demonstrated that blood can be stored on paper for long periods, retaining some irnmunoreactivity.1 However, false negatives may occur in the low titre rangeThe method of CSF storage we describe could have wide applications in neuroinfections. Neuroimmunology Laboratory, National Institute of Neurology of Mexico, 14410 Mexico 22, DF 1. Rosas N, Sotelo J, Nieto D. ELISA in the diagnosis of
ESPERANZA GARCIA JULIO SOTELO neurocysticercosis Arch Neurol
1986; 43: 353-56.
Soulsby EJ, Sheelagh L. Applications of immunological methods in helmintology. In. Weir DM, Herzenberg LA, Blackwell C, Herzenberg LA, eds. Handbook of experimental immunology, vol 4. Oxford: Blackwell, 1986: 123: 1-21. 3. Woller A, DeSavigny D. Diagnostic serology of tropical parasitic diseases. J Immunol
2.
Methods 1981; 46: 1-29.
NORMAL 24-HOUR VARIATION IN ATRIAL NATRIURETIC PEPTIDE
SIR,-Atrial natriuretic peptides (ANPs) are believed to play an important part in the regulation of blood pressure, blood volume, and sodium retention. There have been several reports of ANP concentrations in various physiological and pathological conditions since radioimmunoassays specific for ANP have been developed.’ We report normal ANP fluctuation over 24 hours in human plasma. We investigated 15 healthy volunteers aged 21-23 years. Written informed consent was obtained. All subjects were on a normal diet containing no excess salt and were not taking any drugs. They pursued their usual activities but were discouraged from taking vigorous exercise. Venous blood was taken at 2000, 2400, 0800, 1200, 1600, and 2000 h. ANP was measured by Zhang and colleagues’ radioimmunoassay.2 The mean plasma ANP concentration (figure) was lowest (7-9 pg/ml) at 1200 h and highest
possibility
of a chemical interaction
resulting in
a
colourless,
soluble and undesirable byproduct is not excluded.
compatibility used to be made for antiemetic and mixtures 34but several interactions were uncovered.5 diamorphine Cyclizine and diamorphine mixtures proved to be liable to precipitate or crystallise if the concentration of either drug was above 25 mg/ml, although the concentration of the second drug was below 10 mg/ml. The compatibility studies also uncovered a risk of Claims of
metoclopramide degradation if this was mixed with diamorphine, precipitation in a haloperidol and diamorphine
and the risk of
mixture with a loss of 58% of the haloperidol from solution. The enthusiasm for mixing drugs together in subcutaneous infusions should be tempered until further compatibility studies can be completed. St Oswald’s Hospice,
CLAUD F. B. REGNARD KATHRYN MANNIX
Gosforth, Newcastle upon Tyne NE3 1EE
1. de Sousa E, Jepson BA. Midazolam in terminal care. Lancet 1988; i: 67-68. 2. Martindale: the extra pharmacopoeia. 28th ed. London: Pharmaceutical Press, 1982: 801. 3. Hutchinson HT, Leedham GD, Knight AM. Continuous subcutaneous analgesics and antiemetics in domiciliary terminal care. Lancet 1981; ii: 1279. 4. Oliver DJ. The use of the syringe driver in terminal care. Br J Clin Pharmacol 1985; 20: 515-16.
5.
Regnard C, Pashley S, Westrope F. Antiemetic/diamorphine mixture compatibility in infusion pumps. BrJ Pharm Pract 1986; 8: 218-20.
CONTINUOUS CLEARANCE OF HIV IN A VERTICALLY INFECTED CHILD
SiR,—The proportion of children infected prenatally with HIV who lose their antibodies but remain HIV carriers is unknown. We report virological and clinical data on a healthy 18-month-old congenitally HIV-infected child. The female baby was born in December, 1987, of an HIVinfected drug-addict mother and HIV-negative father. The mother is symptom-free. Absolute lymphocyte count, lymphocyte subsets, monocytes, and platelet count were normal at birth and on five occasions up to May, 1989. The child was not breast-fed or vaccinated. The T 4/T ratio increased from 1-46 at birth to 2.76 in May, 1989. At birth the HIV-antibody pattern of the mother and child was identical. Subsequent tests showed a continuous decrease of serum antibody concentrations in the child: only weak positive tests were obtained by ELISA and western-blotting by seven months after birth, and the indirect immunofluorescence test was negative at that time. Viral p24 antigen in plasma was never detected. A high number of unstimulated cord blood lymphocytes screened for viral antigen expression tested positive (anti-p24, 7/68; anti-pl7, 2/300, anti-gpl20, 5/57). At 18 months no positive cells could be identified in PBMC (peripheral blood mononuclear cells) by any of the three monoclonal antibodies used. In virus culture cord-blood lymphocytes showed a strong cytopathic effect with typical syncytia formation 3 days after co-cultivation. At this time p24 antigen became detectable in culture supernatant, reaching a peak at about 10 days, whereas at 12 months the cytopathic effect occurred later and p24-antigen concentrations were much lower
than at birth (figure). On both occasions viral DNA in PBMC was detected by PCR (polymerase chain reaction). The virus was a high-replicating, syncytia inducing type at birth, and could be easily transfected onto a permanent T-cell line (Sup T1). At 12 months the virus was slow replicating and could not be propagated on Sup Tl. In April and May, 1989, virus cultures and PCRs were negative. The mother’s lymphocytes were negative for HIV at the time of delivery. The disappearance of HIV in a congenitally infected child is notable. The striking cytopathic effect in the first virus isolation with cord blood seen after only three days could be the result of a high number of infected cells rather than a rapidly replicating virus type. The underlying mechanisms for the disappearance of HIV might be explained as immunological tolerance or as an impaired specific immune response to HIV, in that cytotoxic T lymphocytes (CTLs) and/or antibody production might be suppressed.1 The possible absence of a specific immune response could have been a major advantage for the host since CD depletion may be caused by CTLs and/or antibody-dependent cellular cytotoxicity.2 The rise in the T4/Tg ratio may be indirect evidence for this. The shift from a low-replicating, non-syncytia-inducing to a high-replicating-syncytia-inducing virus type, is commonly seen in individuals proceeding to the final stages of AIDS.3,4 The reverse fmding in our patient could be the result of a continuous clearing of HIV subtypes. High-replicating virus types may be eliminated more efficiently than low-replicating subtypes, which are less expressed on the infected cell surface and therefore may be detected and eliminated at a slow rate.5 Alternatively, there may be a shift in the cell reservoir of the virus.6 An initially high-replicating mainly lymphotropic virus could have been depleted by the immune defence and a low-replicating more monocytotropic subtype selected. Therefore the clearing of HIV from the peripheral blood could indicate another stage of the incubation period. It remains to be seen whether the infection status in this child reflects viral latency or silent viral persistence. One possibility to be considered is that the virus load is cleared entirely in some cases and that the once infected children become HIV negative.
Institute for Clinical and Molecular Medicine Clinic III, and Children’s and Polyclinics, University of Erlangen-Nurnberg, 8520 Erlangen, West Germany
Virology,
ANDREAS BAUR NORBERT SCHWARZ SYLVIA ELLINGER KLAUS KORN THOMAS HARRER KARLA MANG
GERHARD JAHN
Jamieson BD, Ahmed R. T-cell tolerance: exposure to virus in utero does not cause a permanent deletion of specific T-cells. Proc Natl Acad Sci USA 1988; 85: 2265-68. 2. Germain RN. Antigen processing and CD4 T-cell depletion in AIDS. Cell 1988; 54: 1.
441-44. 3. Tersmette M, Gruters
R, De Wolf F,
et
al. Evidence for
a
role of virulent human
immunodeficiency virus (HIV) variants in the pathogenesis of acquired immunodeficiency syndrome: studies on sequential HIV isolates. J Virol 1989; 63: 2118-25. 4. Tersmette M,
5.
Lange JMA, de Goede REY, et al. Association between biological properties of human immunodeficiency virus variants and risk for AIDS and AIDS mortality. Lancet 1989; i: 983-85. Leonard R, Zagury D, Desportes I, et al. Cytopathic effect of human immunodeficiency virus in T4 cells is linked to the last stage of virus infection. Proc
Natl Acad Sci USA 1988; 85: 3570-74. 6. McElrath MJ, Pruett JE, Cohn ZA. Mononuclear phagocytes of blood and bone marrow: comparative roles as viral reservoirs in human immunodeficiency virus type 1 infections. Proc Natl Acad Sci USA 1989; 86: 675-79.
RENAL INSUFFICIENCY WITH NEBULISED PENTAMIDINE
SIR,-Dr Miller and colleagues (June 3, p 1273) report the first of acute renal failure associated with nebulised pentamidine. We report a patient in whom nebulised pentamidine seems to be responsible for renal insufficiency. A 59-year-old HIV-1-positive man was admitted for Pneumocystis carinii pneumonia. He was initially treated by intravenous trimethoprim (1-92 g daily) and sulfamethoxazole (9-600 g daily). This treatment was withdrawn because of severe skin reaction. Intramuscular pentamidine was begun (4 mg/g daily). Before this therapy, blood urea was 57 mmol/1 and creatinine 79 case
Days
of cultivation
T-co-cultivation with neg Concentration
of
PMBC
p24 antigen and cytopathic effect child at birth (A) and at twelve months (B).
(CPE)
in the
Arrows = time of CPE. Cells prestimulated with phytohaemagglutinin
(PHA) for 3 days before co-cultivation with negative PBMC.
1046
pmol/1. During the first week, blood urea and creatinine levels progressively increased to 7-3 mmol/1 and 123 Eunol/1, respectively, and intramuscular pentamidine was replaced by nebulised pentamidine (240 mg daily). Nonetheless, renal insufficiency progressed (urea 11-11 mmol/1; creatinine 140 umol/1) and after one more week, pentamidine was withdrawn and replaced by a progressive dose of trimethoprim/sulfamethoxazole. Urinalysis was unremarkable and no other cause of renal dysfunction was identified during nebulised pentamidine. Blood urea and creatinine levels rapidly returned to pretreatment values. Renal insufficiency is known to occur with parenteral pentamidine.1 Since in our patient renal insufficiency progressed despite the use of nebulised pentamidine, we conclude that this form is also contraindicated in such patients. Service of Internal Medicine, Hopital de la Pitié, Pans 75013, France
CATHERINE CHAPELON GILLES RAGUIN CHRISTIAN DE GENNES
1. Sattler FR, Cowan R, Neilsen DM, et al. Trimethoprim-sulfamethoxazole compared with pentamidine for treatment of Pneumocystis carinii pneumonia in the acquired immunodeficiency syndrome. Ann Intern Med 1988; 109: 280-87.
NICOTINE AND TOURETTE’S SYNDROME
SIR,-Sanberg et all reported two children with Tourette’s syndrome who responded to the addition of nicotine to standard treatment. We report striking improvement of Tourette’s symptoms in a smoker, presumably as a result of nicotine in cigarettes. A 21-year-old man with Tourette’s syndrome was first seen by us in 1988. Tourette symptoms had begun at age 8 years, with eye-blinking and a lateral head twitch. Typical progression of symptoms followed, including onset of vocal tics at age 9 years and more complex motor tics such as contractions of leg and abdominal muscles by age 10, when Tourette’s syndrome was diagnosed. Other medical problems include abnormal genitourinary tract development evidenced by bilateral ureter reimplantation at age 2 years and repair of two abdominal hernias and undescended testes at age 3. Hypospadias was also noted. The patient has a slight build (169 cm tall and 43-1kg weight) with noticeable spinal curvature and narrow shoulders. Facial dysmorphologies including low-set ears and asymmetrical jaw and orbits. Karyotyping at 550 band resolution revealed a normal 46 XY male chromosome complement. He had a history of bronchitis and asthma. Initial treatment with haloperidol was unsuccessful because of oversedation. Subsequent treatment with clonidine and pimozide were also unsuccessful, partly because of non-compliance. At age 16 the patient began to smoke cigarettes and progressed to 20 a day. Both the patient and his immediate family reported that Tourette symptoms became less severe in the absence of other medication. In January, 1989, the patient gave up smoking because of concern about respiratory problems, but symptoms of Tourette’s reappeared in a milder form than previously. We suggest that the cessation of symptoms was due to nicotine received during smoking. Reappearance of symptoms was the result of stopping smoking, which argues against spontaneous remission as an alternative explanation. Nicotine is a psychoactive drug2 with dopamine-like effects.3 The observation that Tourette’s symptoms are responsive to nicotine has implications for the aetiology and treatment of the syndrome. Nicotine might be useful in other neuroleptic responsive disorders. Department of Psychiatry, Washington University School of Medicine, St Louis, Missouri 63110, USA
1. Sanberg PR, Fogelson HM,
ERIC J. DEVOR KEITH E. ISENBERG
Manderscheid PZ, Parker KW, Norman AB, McConville BJ. Nicotine gum and haloperidol in Tourette’s syndrome. Lancet 1988; i: 592. 2. Jones RT. Tobacco dependence. In: Meltzer HY, ed. Psychopharmacology: the third generation of progress. New York: Raven Press, 1987: 1589-95. 3. Lapin EP, Maker HS, Sershen H, Hurd Y, Lajtha A. Dopamine-like action of nicotine: lack of tolerance and reverse tolerance. Brain Res 1987, 407: 351-63.
STORAGE OF CEREBROSPINAL FLUID ON PAPER
SIR,-Diagnosis of infectious diseases of the nervous system by enzyme-linked immunosorbent assay (ELISA)’ on cerebrospinal fluid (CSF) is difficult in countries that have few laboratories doing these tests. In such circumstances reference centres have had to be set up, and preservation and transportation of CSF for immunodiagnosis is costly and difficult, especially in underdeveloped countries where infectious diseases are endemic. We report the storage of CSF on ordinary paper for mailing to reference centres. 1 ml of CSF is placed on white paper measuring 4 x2 cm. The paper is then left to dry at room temperature for about 3 h, the patient’s name and code number being recorded in pencil on the paper. The paper is cut in the laboratory into eight strips of 205 cm. To test this form of storage we selected for ELISA testing 108 CSF samples from patients with neurocysticercosis (NCC) positive to cysticercus antigens, and 11 from patients with subacute sclerosing panencephalitis (SSPE) positive to measles antigens. In addition, 210 CSF samples from patients with various neurological disorders were negative controls. A 96-well microtitre plate was loaded with cysticercus antigen, and the paper strips folded in a zig-zag were placed in the wells. 200pi of phosphate-buffered saline (PBS) polysorbate 20 were added to each well and left overnight. The strips were then removed and the wells washed. 200 1 of a mixture of 1/1000 rabbit anti-human IgG plus 1/1000 rabbit anti-human IgM alkaline phosphatase conjugates diluted in PBS-polysorbate 20 were added and left for 90 minutes, the wells were washed, and colour was developed with p-nitrophenyl substrate. Results above 0-40 optical density (OD) at 420 nm were regarded as positive. All paper strips had remained at room temperature for 15 days before testing. The fresh CSF samples were also tested by ELISA, at a dilution of 1 in 30 in PBS. We also tested by ELISA fresh and stored CSF samples from SSPE patients for measles antigens. In fresh CSF samples, 108 were positive for cysticercosis by ELI SA and 210 were negative. When the test was repeated with the storage strips, 105 samples from NCC patients remained positive and all negative samples remained negative, giving 97% concordance for true positives and 100% concordance for true negatives; results obtained for measles virus in SSPE patients showed 100% and 98%
concordance, respectively. Previous studies have demonstrated that blood can be stored on paper for long periods, retaining some irnmunoreactivity.1 However, false negatives may occur in the low titre rangeThe method of CSF storage we describe could have wide applications in neuroinfections. Neuroimmunology Laboratory, National Institute of Neurology of Mexico, 14410 Mexico 22, DF 1. Rosas N, Sotelo J, Nieto D. ELISA in the diagnosis of
ESPERANZA GARCIA JULIO SOTELO neurocysticercosis Arch Neurol
1986; 43: 353-56.
Soulsby EJ, Sheelagh L. Applications of immunological methods in helmintology. In. Weir DM, Herzenberg LA, Blackwell C, Herzenberg LA, eds. Handbook of experimental immunology, vol 4. Oxford: Blackwell, 1986: 123: 1-21. 3. Woller A, DeSavigny D. Diagnostic serology of tropical parasitic diseases. J Immunol
2.
Methods 1981; 46: 1-29.
NORMAL 24-HOUR VARIATION IN ATRIAL NATRIURETIC PEPTIDE
SIR,-Atrial natriuretic peptides (ANPs) are believed to play an important part in the regulation of blood pressure, blood volume, and sodium retention. There have been several reports of ANP concentrations in various physiological and pathological conditions since radioimmunoassays specific for ANP have been developed.’ We report normal ANP fluctuation over 24 hours in human plasma. We investigated 15 healthy volunteers aged 21-23 years. Written informed consent was obtained. All subjects were on a normal diet containing no excess salt and were not taking any drugs. They pursued their usual activities but were discouraged from taking vigorous exercise. Venous blood was taken at 2000, 2400, 0800, 1200, 1600, and 2000 h. ANP was measured by Zhang and colleagues’ radioimmunoassay.2 The mean plasma ANP concentration (figure) was lowest (7-9 pg/ml) at 1200 h and highest