Ana Lia Taratuto

Instituto de Investigaciones Neurológicas, Fundación FLENI, Argentina

Since the first Argentine CJD report in 1945, only 9 cases were reported up to 1979 in our country (1-4).

The Neuropathological Referral Centre (NRC) was established in our laboratory in 1983 following Carleton Gajdusek's suggestion and advice, at the Institute for Neurological Research in Buenos Aires, dealing with cases reported since 1980. Information on handling CJD samples and surgery instruments as well as biopsy or autopsy material, was provided to neurologists, neurosurgeons and pathologists. The first ten biopsy and/or autopsy CJD cases were published in 1989 (all Argentinean cases except two originally from Chile) (5).

By December 1996 a total of 22 cases (21 clinically sporadic and 1 familial originally from Chile) have been confirmed at this NRC (6-7). During the 1980-1996 period, 12 further CJD neuropathologically confirmed cases have been studied by neuropathologists from other institutions in Argentina (11 sporadic and 1 probably iatrogenic due to dura mater transplant), so that a total of 34 definite cases was diagnosed in our country since 1980.

In March 1997, following WHO recommendations, an Epidemiological Surveillance Committee for CJD and other TSEs was set up jointly with the Argentine Neurology and Pathology Societies. No figures or estimates were available until then for the incidence of probable or possible CJD cases in Argentina. Neither could the annual mortality rate be established because there was no National CJD Epidemiological Surveillance Program.

During 1997, there were 7 definite cases (3 biopsies and 4 autopsies). Two were originally from Chile, one familial, the other apparently "sporadic", featuring a codon 200 mutation, PRNP E200K-129MV Apo E 3/3 in both. Another "sporadic" case affected by severe insomnia documented by a polysomnography which showed absence of stages 3, 4 and REM, was also associated to a codon 200 mutation E200K-129 MM (8) (DNA studied at Indiana University by B. Ghetti, P. Piccardo and C. Young). There were 1 probable and 5 possible cases.

During 1998 there were also 7 definite cases (5 biopsies and 2 autopsies), one of them familial, originally from Chile (DNA analysis currently in process), 2 probable and 7 possible cases.

Age range at onset for the 36 cases confirmed at the NRC up to 1998 was 38 to 74 years, with a mean of 56.1 years. There were 19 males and 17 females. Total duration of disease until the neuropathological study (biopsy or autopsy) was 2.5 to 24 months with a mean of 7.6 months. Neurological onset was gradual (weeks or months) in 34 cases and rapid or sudden (days) with a stroke-like episode in only two. At onset, behavioural abnormalities and/or mental deterioration of a week to a year of duration were observed in more than half of the cases, while neurological symptoms predominated in the remainder. Patients developed pyramidal, extrapyramidal, cerebellar and/or visual signs and myoclonus followed by akinetic mutism in their terminal phase. Characteristic EEG was already obtained at pathological diagnosis (biopsy or autopsy) in 18 cases. CT brain scanning and/or MRI showed slight to moderate cortical brain atrophy, mostly diffuse and bilateral with a single unilateral case. One of the cases with MRI studies exhibited unilateral parieto-occipital hyperintensity in the T2-weighted images and 2 cases, bilateral hyperintensity in the basal ganglia. Minor ischemic changes were reported on MRI in at least 3 cases.

Out of the 36 cases referred to the NRC as clinically probable or possible CJD, 25 were studied by means of biopsy (including 3 stereotactic) and 12 by autopsy (1 case by both biopsy and autopsy). Biopsy and autopsy samples were autoclaved or treated with formic acid after formaldehyde or glutaraldehyde fixation. Paraffin sections were stained with hematoxylin-eosin, acid-Schiff, Luxol fast blue or Heidenhain Woelcke, Bielschowsky stains and representative sections immunoreacted with GFAP, tau, ß-amyloid and PrP with 3F4 monoclonal antibody (the latter for the 1997-1998 cases). All biopsies and autopsies (except for the one from the single insomnia case in which the main lesions involved the thalami) showed unequivocal spongiform changes, neuronal depletion of variable intensity, as well as astroglial hyperplasia in the brain cortex, the cerebellar cortex and the subcortical grey matter. Vacuoles were sharp, circular or ovoid, 2-20 microns in the diameter. Cortical involvement was particularly prominent in layers 3 and 5 and even more pronounced in the depth of the sulci. In some of the cases focal confluent vacuoles were present mimicking grape-like microcavitations. Prominent vacuolar changes and gliosis featuring focal "status spongiosus" in the cortex were only observed in two cases. Neuronal loss was variable while cortical and basal ganglia astrocytic hyperplasia was particularly evident. Only a few astrocytes could be observed in the underlying white matter. Tangles, ß-amyloid plaques and ß-amyloid angiopathy were absent from the neocortex and white matter demyelination was not observed. At electron microscopy, vacuoles of different sizes were seen in the cortex, some fusing or coalescing into larger ones, most of them containing bridging and fragmented membranes and vesicles. Fluffy amorphous material was also observed in some vacuoles. On occasion, vacuoles were present in the neuronal cytoplasm or in the pre or postsynaptic processes. Lipofucsin was also observed in neurons.

At postmortem brain examination, slight diffuse convolutional atrophy was present as well as ventricular dilatation in some cases. Cortical lesions were sparsely scattered and variable, in some cases predominantly involving frontal and temporal lobes, while in others occipital cortex and calcarine area. Cerebellum showed spongiform changes in the molecular layer. Purkinje cell loss was observed only focally and there was slight granular cell loss in the vermis as well as in the hemispheres.

The 1998 definite case affected by severe Insomnia showed preferential thalamic involvement with moderate spongiform changes, neuronal loss and severe gliosis (8). Occasionally, Purkinje cell axonal torpedos were observed. Substantia Nigra was preserved, no Lewy bodies could be disclosed. Pyramidal tract degeneration was absent and no myelin changes were observed in the white matter. PrP immunostaining was synaptic, perivacuolar and/or perineuronal, particularly prominent in the CJD 200 cases. A single 1998 "sporadic" case currently awaiting DNA studies displayed PrP plaques. In two of the autopsied cases, there was also arteriosclerosis with mild focal ischaemic changes.

To date, Gerstmann-Straussler-Scheinker disease has not been reported. No atypical cases similar to the new CJD variant (vCJD) described in the UK and France are known.

For the WHO Consultation on Clinical and Neuropathological Characteristics of the New Variant of CJD and other Human and Animal Transmissible Spongiform Encephalopathies, on May 14-16, 1996, Geneva, we sent a questionnaire to neuropathologists in Brazil, Mexico, Uruguay and Venezuela in respect to the CCJD surveillance. At that time, none of those countries had offcial CJD surveillance, nor have atypical variants (vCJD) been reported to date (6).

Following an invitation to attend the WHO consultation on CJD and other TSEs in Geneva, on May 1996, an effort was made to divulge the need for CJD surveillance, vCJD characteristics and WHO recommendations among neurologists, neurosurgeons, pathologists and National Health Care authorities in Argentina.

Accordingly, the Human TSE preventive program in Argentina was set up and initiated the following activities:

1. Mailing of retrospective and prospective CJD reports to all neurologists, neurosurgeons and pathologists in Argentina with the purpose of organizing a registry as well as divulging biosafety measures related to biopsies and autopsies, handling of specimens and decontamination of materials (Despite of a high diagnostic yield and no morbility, following WHO we do not recommend brain biopsy, except for the alternative diagnosis of treatable diseases.(9) )

2. Dispersion of such information through Neuro-Web-lnternet of the Argentine Neurological Society (http//priv.roche.com.ar/neuroweb/).

3. Organization of Clinicopathological conferences on CJD cases, of symposia and posters related to CJD surveillance, at the World Congress of Neurology, Buenos Aires, in September 1997 (7).

4. Similar activity at the 1997 Argentine Society of Pathology Meeting, in Rosario, Argentina, in November 1997.

5. Attendance at the European Community Meeting, Biomed2 on Human Prion Diseases, in Vienna, in December 1996 and June 1999. (A. L. Taratuto).

6. Membership in the Argentine Scientific Advisory Committee and attendance BSE Meeting of the Secretary of Agriculture, Livestock, Fisheries and Food, in Buenos Aires, September 1997 and November 1998 (A. L. Taratuto).

7. Attendance of the Special Course on Prion Protein Diseases, of the American Association of Neuropathologists, in June 1997 (G. Sevlever and A. L. Taratuto).

8. Attendance by invitation at the WHO Consultation on the Global Surveillance of Human TSEs, in Geneva, in February 1998 (M. Somoza). During this meeting data related to 1997 Argentine CJD surveillance was presented and there was a recommendation to appoint the Argentine team as a WHO Regional Collaboration Centre.

9. Organization of an International Workshop on TSEs for South American Countries, together with the WHO (M. Zeidler and M. Ricketts), the Pan American Health Organisation (PAHO), and the Pan American Institute for Protection of Foodstuffs and Zoonosis (INPPAZ) in Martinez, Buenos Aires, on March 16-18, 1998). This workshop was attended by representative neurologists, pathologists and epidemiologists from most Latin American Countries. Among other recommendations, the Argentine CJD Neuropathological Referral Centre was proposed as a WHO Regional Collaboration Centre.

10. Since May 1996, following WHO recommendations, several interviews were held by the coordinators with the National Public Health Authorities to stress the need of CJD surveillance.

11. The National Secretary of Public Health set up in February 1998 a Scientific Advisory Committee on CJD and other human TSEs which includes representative members of both Neurology and Pathology Societies of the Surveillance Committee.

12. Distribution of information on the need to standardise EEG criteria to be adopted for CJD diagnosis through the Argentine Society of EEG and Clinical Neurophysiology. These criteria are WHO suggestions. Dr.C.Blanc, who is member of both Neurology and EEG societies is now performing the central review of the EEGs.

13. Distribution of forms to report possible or probable cases of CJD, to 1500 members of the Argentine Association of Psychiatrists, through their Journal.

14. Organization of Satellite Symposium on Human TSEs: which discussed neurological, EEG, psychiatric and neuropathological aspects of CJD as well as surveillance. Projection of a video on kuru, BSE, and vCJD with further discussion at the National Argentine Neurological Society Congress in November 1998 in Corrientes, Argentina.

15. Workshop on the same subject with regional epidemiologists and Public Health authorities at the above Congress.

16. Organization of Conference on Human TSEs, Neuropathology and Surveillance at the annual meeting of the Argentine Society of Pathology, Buenos Aires, in November 1999.

17. Attendance by invitation at the WHO Consultation on Caring for Patients and Hospital Infection Control in Relation to Human TSEs Meeting, in Geneva, March 1999 (Dr Taratuto)

18. When requested by press media, statement were issued by the CJD Committee to clear up common misunderstandings on CJD, vCJD and BSE in the public.

In spite of our persistent efforts, so there were no national funds allotted to CJD surveillance, neuropathological diagnosis or pertinent molecular biology research.

We have just recently (July 1999) obtained a grant from the National Secretary of Science and Technology .

- In order to facilitate activities to assist WHO at global and regional levels, and thus strengthen surveillance of CJ and related diseases, we received the amount of 6,000 dollars (out of 10,000 for the October 1998-1999 period). Accordingly, PrP Western Blot analysis was set up at our laboratory, which is already equipped with BSL-2 facilities, and uses BCL3 procedures. For that purpose, Dr. Pedro Piccardo from Indiana University gave us valuable advice on technical workup.

1. V Dimitri, J Aranovich. Contribución al conocimiento de la degeneración corticoespinal o "pseudoesclerosis espástica de A. Jakob. Rev Neurol Arg 10:225,1945.

2. GRP Abiusi, A Scarlatti, A Salama, JC Ortiz de Zarate. Encefalopatía espongiosa presenil o Enfermedad de Jakob-Creutzfeldt. Rev Neurol Arg 4: 16,1978.

3. M Sarcuno, E Hiskin. Aporte a trabajos presentados sobre enfermedad de Creukfeldt Jakob: Nuestra experiencia en dos casos. Formas clínicas. Resumenes de trabajos. Actas XVII Congreso Argentino de Neurología,1976.

4. G. Nogueira, A Sundblad, O Gómez Molina. Letters to the Editor Archives of Neurology 36: 181,1979.

5. AL Taratuto, P Piccardo, R Leiguarda, R Granillo, A Monti, A Scarlatti, A Leits, C Morasso, C Marquez Vigo, J Vila, A Gutierrez. Creutzfeldt-Jakob Disease. Report of 10 neuropathologically verified cases in Argentina. Medicina 49:293-303,1989.

6. AL Taratuto. Argentina and other Latin American countries in National reports on CJD related disorders in Report of a WHO Consulbtion on Clinical and Neuropathological Characteristics of the New Variant of CJD and the other Human and Animal Transmissible Spongiform Encephalopathies. Geneva, Switzerland 14 to 16 May 1996. World Health Organization.

7. AL Taratuto, G Sevlever, M Schultz. Creutzfeldt Jakob Disease in Argentina: a Neuropathological perspective. Journal of the Neurological Sciences.Suppl Vol 150 S55,1997.

8. AL Taratuto, P Piccardo, G Sevlever, M Schultz, F Reich, A Leuzzi, M.Ruggiero, G Abecassis, M Engelmann, AM Garcia, S Capellari, E Lugaresi, P Gambetti, SR Dlouhy, B Ghetti. Insomnia in Creutzfeldt Jakob Disease (CJD) E200K with thalamic involvement. Journal of Neuropath. and Experimental Neurol. May 1999;58(5) 555.

9. International Workshop on Transmissible Spongiform Encephalopathies (CJD-BSE). Argentina, March 16- 18,1998. Recommendations.

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