Ocular abnormalities in the mucopolysaccharidoses after bone marrow transplantation. Longer follow-up

OBJECTIVE

The purpose of the study was to provide longer follow-up of ocular findings in patients with mucopolysaccharidoses (MPS) after bone marrow transplantation (BMT).

DESIGN

The study design was a retrospective 6-year cohort evaluation.

PARTICIPANTS

Twenty-three patients with MPS (19 with MPS type I-H, 3 with MPS type III, 1 with MPS type VI) were studied.

INTERVENTION

Bone marrow transplantation was performed.

MAIN OUTCOME MEASURES

The following outcome measures were considered: vision, slit-lamp biomicroscopic and funduscopic examinations, intraocular pressure, electroretinography (ERG), and retinoscopy.

RESULTS

Thirteen (81%) of 16 patients showed ERG improvement in the first year. However, all patients showed slowly progressive decline of the ERG over longer follow-up. Other ocular findings included optic atrophy (n = 7 patients), disc edema (n = 6 patients), strabismus (n = 6 patients), nystagmus (n = 6 patients), cataract (n = 3 eyes), keratoconjunctivitis sicca (n = 4 eyes), ocular hypertension (n = 2 eyes), and glaucoma (n = 2 eyes).

CONCLUSIONS

The MPS are rare and heterogeneous disorders characterized by progressive retinal degeneration and blindness. Ocular abnormalities can occur as a result of the disease or as a consequence of BMT. Successful BMT has been shown to improve systemic health, but this may not reflect continuing ocular status and retinal function. Despite early improvement in ERG function, longer follow-up suggests progressive retinal decline.

Hematopoietic stem-cell transplantation in globoid-cell leukodystrophy

BACKGROUND

Globoid-cell leukodystrophy is caused by a deficiency of galactocerebrosidase, which results in progressive central nervous system deterioration. We investigated whether allogeneic hematopoietic stem-cell transplantation can provide a source of leukocyte galactocerebrosidase and thereby prevent the decline of central nervous system function in patients with the disease.

METHODS

Five children with globoid-cell leukodystrophy (one with the infantile type and four with late-onset disease) were treated with allogeneic hematopoietic stem-cell transplantation. Measurement of leukocyte galactocerebrosidase levels, neurologic examinations, neuropsychological tests, magnetic resonance imaging of the central nervous system, cerebrospinal fluid protein assays, and neurophysiologic measurements were performed before and after transplantation, with follow-up ranging from one to nine years.

RESULTS

Engraftment of donor-derived hematopoietic cells occurred in all patients and was followed by restoration of normal leukocyte galactocerebrosidase levels. In the four patients with late-onset disease, the central nervous system deterioration was reversed, and in the patient with the infantile form of the disease, signs and symptoms have not appeared. Magnetic resonance imaging showed a decrease in signal intensity in the three patients with late-onset disease who were assessed both before and after transplantation. Abnormalities in cerebrospinal fluid total protein levels were corrected in three patients with late-onset disease and substantially reduced in the patient with the infantile form.

CONCLUSIONS

Central nervous system manifestations of globoid-cell leukodystrophy can be reversed by allogeneic hematopoietic stem-cell transplantation.

Hurler syndrome: II. Outcome of HLA-genotypically identical sibling and HLA-haploidentical related donor bone marrow transplantation in fifty-four children. The Storage Disease Collaborative Study Group

Untreated patients with Hurler syndrome (MPSIH) experience progressive neurologic deterioration and early death. Allogeneic bone marrow transplantation (BMT) ameliorates or halts this course. The Storage Disease Collaborative Study Group was formed to evaluate the effectiveness and toxicity of BMT. Effectiveness was defined as engrafted survival with continuing cognitive development. Fifty-four patients deficient in leukocyte alpha-L-iduronidase enzyme activity (median age, 1.8 years; range, 0.4 to 7.9) received high-dose chemotherapy with or without irradiation and BMT from HLA-genotypically identical sibling (GIS) or HLA-haploidentical related (HIR) donors between September 16, 1983 and July 14, 1995; all children were included in this report. Thirty-nine of 54 patients (72%) engrafted following the first BMT. The probability of grade II to IV acute graft-versus-host disease (GVHD) at 100 days was 32% for GIS and 55% for HIR patients. The probability of extensive chronic GVHD was 0% for GIS and 24% for HIR patients. The actuarial probability of survival at 5 years was 64% for all patients, 75% for GIS patients, 53% for HIR patients, and 53% for patients with donor marrow engraftment. The baseline Mental Developmental Index (MDI) was examined both for children less than and greater than 24 months of age at BMT. Children transplanted before 24 months had a mean baseline MDI of 78, while those transplanted after 24 months had a mean baseline MDI of 63 (P = . 0002). Both baseline and post-BMT neuropsychologic data were available for 26 of 30 engrafted survivors. Of 14 patients transplanted before 24 months of age, nine demonstrated developmental trajectories that were normal or somewhat slower than normal. In contrast, of 12 patients transplanted after 24 months of age, only three showed developmental trajectories that were normal or somewhat slower than normal (P = .01). For children with a baseline MDI greater than 70, there was a significant correlation between the MDI at follow-up study and leukocyte alpha-L-iduronidase enzyme activity (P = .02). Children were more likely to maintain normal cognitive development if they were fully engrafted following BMT from a donor with homozygous normal leukocyte alpha-L-iduronidase enzyme activity. Children who developed acute GVHD of grade II or worse had significantly poorer cognitive outcomes (P < .009). No difference in the post-BMT MDI was observed between patients whose preparative therapies did (n = 10; radiation dose, 300 to 1,400 cGy) or did not (n = 16) include radiation. We conclude that MPSIH patients, particularly those less than 24 months of age with a baseline MDI greater than 70, can achieve a favorable long-term outcome with continuing cognitive development and prolonged survival after successful BMT from a related donor with homozygous normal enzyme activity.

Surgical treatment of carpal tunnel syndrome and trigger digits in children with mucopolysaccharide storage disorders

The role of surgical intervention for carpal tunnel syndrome (CTS) and trigger digits in children with mucopolysaccharide storage disorders (MPSDs) has not been clearly defined, particularly as the treatment of the underlying disease has advanced to include bone marrow transplantation. This study reviews our experience in the treatment of CTS and trigger digits in 22 children with MPSDs who were evaluated for CTS by electromyographic (EMG)/nerve conduction velocity (NCV) testing. Seventeen children were diagnosed with CTS by EMG/NCV testing and were treated with bilateral open surgical release with or without flexor tenosynovectomy. The EMG/NCV testing revealed normal results in 5 patients who are subsequently being monitored. Forty-five digits in 8 children were diagnosed clinically with trigger digits. Nineteen digits were treated by annular pulley release alone. Twenty-six digits were treated by annular pulley release with partial flexor digitorum superficialis tendon resection. The average age at the time of hand surgery was 6.3 years, and at the time of follow-up, 9.6 years. Postoperative EMG/NCV testing in 7 children showed 1 with improvement and 6 with normalization. None of the patients undergoing carpal tunnel release went on to develop thenar atrophy or absent sensibility, as has been reported in untreated cases. Patients were evaluated for triggering digits both by preoperative tendon palpation and by intraoperative flexor tendon excursion at the time of open carpal tunnel release. All patients undergoing trigger release had improved active digital flexion seen at the final follow-up visit. Because of the very high incidence of CTS and trigger digits in this population, the authors currently recommend routine screening of EMG/NCV for all children with MPSDs. Early surgical intervention for nerve compression and stenosing flexor tenosynovitis can maximize hand function in these children.

Syringomyelia in mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome): imaging findings following bone marrow transplantation

We present the imaging findings in a patient with mucopolysaccharidosis (MPS) type VI (Maroteaux-Lamy syndrome) who developed holocord syringomyelia. This represents the only reported case of syrinx formation in a child with MPS VI. Clinical, neurologic and spinal magnetic resonance imaging findings are presented. The patient has maintained a stable clinical and neurologic course over the period following allogeneic bone marrow transplant.

Proton MR spectroscopy and neuropsychological testing in adrenoleukodystrophy

PURPOSE

To determine early signs of disease in patients with childhood-onset cerebral adrenoleukodystrophy (COCALD) with the use of proton MR spectroscopy.

METHODS

Eleven children with posterior COCALD involvement and three children with anterior COCALD involvement were studied with single-voxel proton MR spectroscopy and neuropsychological testing. Findings were compared with those in five healthy control subjects.

RESULTS

Areas of abnormal T2 signal intensity in children with COCALD showed abnormal metabolite ratios relative to those of control subjects as follows: decreased N-acetylaspartate (NAA)/Creatine (Cr) and NAA/Choline (Ch) and increased Ch/Cr. Metabolite ratios from normal-appearing brain regions in the same patients also were abnormal, with reduced NAA/Cr and NAA/Ch and increased Ch/Cr values. The mean metabolite ratios in normal-appearing regions were between those in the abnormal regions and those found in the control subjects. Statistical comparison of these ratios with neuropsychological test scores, which are specific for anterior and posterior brain functions, showed a significant correlation with the abnormal metabolite ratios. Our results indicate that the normal-appearing brain regions in these patients are metabolically abnormal.

CONCLUSION

Proton MR spectroscopy could be a useful noninvasive tool to evaluate extent of disease in patients with COCALD.

Molecular heterogeneity of late-onset forms of globoid-cell leukodystrophy

Globoid-cell leukodystrophy (GLD) is an autosomal recessive inherited disorder caused by the deficiency of galactocerebrosidase, the lysosomal enzyme responsible for the degradation of the myelin glycolipid galactocerebroside. Although the most common form of the disease is the classical infantile form (Krabbe disease), later-onset forms also have been described. We have analyzed the galactocerebrosidase gene in 17 patients (nine families) with late-onset GLD and in 1 patient with classical Krabbe disease. Half of the patients were heterozygous for the large gene deletion associated with the 502C-->T polymorphism, the most common mutation in infantile patients. Several novel mutations that result in deficient galactocerebrosidase activity were also identified in these patients. They include the missense mutations R63H, G95S, M101L, G268S, Y298C, and I234T; the nonsense mutation S7X; a one-base deletion (805delG); a mutation that interferes with the splicing of intron 1; and a 34-nt insertion in the RNA, caused by the aberrant splicing of intron 6. All of these genetic defects are clustered in the first 10 exons of the galactocerebrosidase gene and therefore affect the 50-kD subunit of the mature enzyme. Studies on the distribution and enzymatic activity of the polymorphic alleles 1637T/C (I546/T546) provided support for previous data that had indicated the existence of two galactocerebrosidase forms with different catalytic activities in the general population. Our data also indicate that the mutations occur preferentially in the "low activity" 1637C allele.

Outcome of unrelated donor bone marrow transplantation in 40 children with Hurler syndrome

Long-term survival and improved neuropsychological function have occurred in selected children with Hurler syndrome (MPS I H) after successful engraftment with genotypically matched sibling bone marrow transplantation (BMT). However, because few children have HLA-identical siblings, the feasibility of unrelated donor (URD) BMT as a vehicle for adoptive enzyme therapy was evaluated in this retrospective study. Forty consecutive children (median, 1.7 years; range, 0.9 to 3.2 years) with MPS I H received high-dose chemotherapy with or without radiation followed by BMT between January 27, 1989 and May 13, 1994. Twenty-five of the 40 patients initially engrafted. An estimated 49% of patients are alive at 2 years, 63% alloengrafted and 37% autoengrafted. The probability of grade II to IV acute graft-versus-host disease (GVHD) was 30%, and the probability of extensive chronic GVHD was 18%. Eleven patients received a second URD BMT because of graft rejection or failure. Of the 20 survivors, 13 children have complete donor engraftment, two children have mixed chimeric grafts, and five children have autologous marrow recovery. The BM cell dose was correlated with both donor engraftment and survival. Thirteen of 27 evaluable patients were engrafted at 1 year following URD BMT. Neither T-lymphocyte depletion (TLD) of the bone marrow nor irradiation appeared to influence the likelihood of engraftment. Ten of 16 patients alive at 1 year who received a BM cell dose greater than or equal to 3.5 x 10(8) cells/kg engrafted, and 62% are estimated to be alive at 3 years. In contrast, only 3 of 11 patients receiving less than 3.5 x 10(8) cells/kg engrafted, and 24% are estimated to be alive at 3 years (P = .05). The mental developmental index (MDI) was assessed before BMT. Both baseline and post-BMT neuropsychological data were available for 11 engrafted survivors. Eight children with a baseline MDI greater than 70 have undergone URD BMT (median age, 1.5 years; range, 1.0 to 2.4 years). Of these, two children have had BMT too recently for developmental follow-up. Of the remaining six, none has shown any decline in age equivalent scores. Four children are acquiring skills at a pace equal to or slightly below their same age peers; two children have shown a plateau in learning or extreme slowing in their learning process. For children with a baseline MDI less than 70 (median age, 2.5 years; range, 0.9 to 2.9 years), post-BMT follow-up indicated that two children have shown deterioration in their developmental skills. The remaining three children are maintaining their skills and are adding to them at a highly variable rate. We conclude that MPS I H patients with a baseline MDI greater than 70 who are engrafted survivors following URD BMT can achieve a favorable long-term outcome and improved cognitive function. Future protocols must address the high risk of graft rejection or failure and the impact of GVHD in this patient population.

Proton MR spectroscopy of childhood adrenoleukodystrophy

PURPOSE

To determine the potential of proton MR spectroscopy to monitor patients with childhood-onset cerebral adrenoleukodystrophy (COCALD).

METHODS

Single-voxel MR spectroscopy was performed in 16 children with COCALD (24 examinations) who had had no treatment and in 7 children (13 examinations) who had had bone marrow transplantation.

RESULTS

In the untreated children with clinically active COCALD, the metabolite ratios N-acetyl-aspartate (NAA)/creatine (Cr) and NAA/choline (Ch) were decreased while Ch/Cr was increased. This trend agrees well with those reported by other researchers, although different experimental sequences and parameters were used in our study. Comparison of these ratios with those from a control group yielded significant differences in the occipital region. In the children who were clinically stable after bone marrow transplantation, the mean levels of the three ratios were between those of the control subjects and the patients with untreated COCALD: the differences in these ratios approached significance. In patients who had been monitored periodically, MR spectroscopy metabolite ratios correlated well with the dementia rating score, reflecting clinical status.

CONCLUSION

There is good correlation between MR spectroscopy metabolite ratios and a patient's clinical status. MR spectroscopy appears to be a useful, noninvasive tool to monitor patients with adrenoleukodystrophy, and it increases the overall sensitivity of MR techniques in clinical applications.

Unrelated donor bone marrow transplantation: influence of HLA A and B incompatibility on outcome

We have studied the outcome of 211 consecutive unrelated donor (URD) bone marrow transplants (BMT) performed at the University of Minnesota (Minneapolis, MN) between May 1985 and December 1992. Ninety patients (43%) received marrow matched serologically at HLA A, B, and DR loci; 86 (41%) received marrow with a major and 32 (15%) marrow with a minor serologic mismatch at the HLA A or B locus. Multivariate analysis revealed that older age had an adverse effect on survival. In younger (age less than 18 years) recipients, survival after fully matched (A, B, and DR sub-type) or major mismatched (A or B locus), DR subtype-matched donor BMT was not significantly different (P = .4; survival: 53% v 41%, respectively, at 3 years). For adults, survival after matched donor BMT was significantly better than that with mismatched donors (P < .01; survival: 30% v 10%, respectively, at 3 years). Formal quality of life assessment by telephone interview demonstrated similar functional status in survivors of URD and related donor (RD) BMT at least 2 years post-BMT. URD BMT provides effective therapy for a variety of lethal hematopoietic diseases that rivals outcome of RD transplant in some cases. Use of URD marrow with a major mismatch at one HLA A or B locus is well tolerated in young, but not in older, recipients. These observations should be used to improve donor selection and counseling for URD BMT candidates.

Microglia: the effector cell for reconstitution of the central nervous system following bone marrow transplantation for lysosomal and peroxisomal storage diseases

Treatment and potential cure of lysosomal and peroxisomal diseases, heretofore considered fatal, has become a reality during the past decade. Bone marrow transplantation, (BMT), has provided a method for replacement of the disease-causing enzyme deficiency. Cells derived from the donor marrow continue to provide enzyme indefinitely. Several scores of patients with diseases as diverse as metachromatic leukodystrophy, adrenoleukodystrophy, globoid cell leukodystrophy, Hurler syndrome (MPS I-H), Maroteaux-Lamy (MPS VI) Gaucher disease, and fucosidosis have been successfully treated following long-term engraftment. Central nervous system (CNS) manifestations are also prevented or ameliorated in animal models of these diseases following engraftment from normal donors. The microglial cell system has been considered to be the most likely vehicle for enzyme activity following bone marrow engraftment. Microglia in the mature animal or human are derived from the newly engrafted bone marrow. Graft-v-host disease activation of the microglia is also of importance. This article will summarize some of the pertinent literature relative to the role of microglia in such transplant processes.

Hematopoietic cell transplantation in fetal lambs with ceroid-lipofuscinosis

Hematopoietic cells from the liver of normal 45-48-day-old fetal lambs (Hb type AA) were transplanted intraperitoneally into 58-60-day-old recipient fetuses (Hb type BB). The recipient fetuses resulted from mating homozygous ceroid-lipofuscinosis affected males with heterozygous, phenotypically normal, females. The sex of the donor fetus was also recorded. At age 2 1/2 months the recipient lambs with ceroid-lipofuscinosis were diagnosed by histopathology of brain biopsies. Monitoring of blood and bone marrow cells showed that an average of 9% of blood cells in ceroid-lipofuscinosis affected recipients were of donor origin. No differences were evident in the clinical course of disease, brain weight, or histopathology of organs between transplanted and non-transplanted lambs with ceroid-lipofuscinosis. Under the conditions of this experiment, transplantation of fetal hematopoietic cells was not beneficial.

The future for treatment by bone marrow transplantation for adrenoleukodystrophy, metachromatic leukodystrophy, globoid cell leukodystrophy and Hurler syndrome

Within the past decade, bone marrow transplantation has been applied to over 200 patients worldwide with the intention of treating storage diseases. Bone marrow transplantation has provided a method for treatment of adrenoleukodystrophy, metachromatic leukodystrophy, globoid cell leukodystrophy and Hurler syndrome. After engraftment, significant improvement in the clinical course of each of these diseases occurs. Survival data of engrafted patients are superior to those of non-transplanted. Engraftment and the resulting enzymatic reconstitution are concordant. Outcomes based on neuropsychological tests indicate continued maintenance and in some cases increase in cognitive function. Magnetic resonance imaging as well as spectroscopic examinations of the brain provide further evidence that positive changes occur in the central nervous system following long-term engraftment. A better quality of life follows engraftment. Greater gains from use of bone marrow transplantation for these particular storage diseases will occur in the future. Earlier diagnosis will allow bone marrow transplantation in the presymptomatic stage at a younger age, providing an enhancement of positive effects noted from such treatment. At the same time, advances in bone marrow technology will serve to reduce the risk factors involved with the bone marrow transplantation process itself. These two factors taken together will be more than additive in providing benefits from use of bone marrow transplantation.

Neuropsychological outcomes of several storage diseases with and without bone marrow transplantation

Neuropsychological assessment is essential in providing documentation of the untreated natural history of storage diseases associated with dementia and quantifying the effectiveness of treatment on central nervous system function. Baseline characterization and outcome of bone marrow transplantation (BMT) for three leukodystrophies and three mucopolysaccharidoses are presented. Results suggests that BMT for Hurler syndrome, adrenoleukodystrophy, and globoid cell leukodystrophy can be effective in preventing dementia if done early enough in the disease. Sanfilippo and Hunter syndromes do not benefit and BMT is not recommended. For metachromatic leukodystrophy, BMT is not recommended for symptomatic early-onset forms of the disease. Further longitudinal follow-up is needed to determine whether the benefits outweigh the risks of BMT for late-onset and preclinical metachromatic leukodystrophy.

Resting Tl-201 scintigraphy in the evaluation of coronary artery disease in children with Hurler syndrome

Severe coronary artery disease may occur early in the course of mucopolysaccharidosis. The authors present radiologic, scintigraphic, and pathologic findings in five patients with Hurler syndrome. Thallium-201 myocardial scintigraphy and selective coronary angiography obtained within 2 days to 6 months were correlated in five patients. Postmortem examination of the coronary arteries was obtained in one patient within hours of angiography. Interobserver agreement on grading of scintigraphic abnormalities was poor. Nonspecific findings on Tl-201 studies included septal abnormalities in all five patients. Scintigraphic findings were corroborated by angiography and postmortem results in only 3 of 5 patients. Our findings suggest that resting Tl-201 scintigraphy has limited value in the detection of coronary artery disease in patients with Hurler syndrome.

Serial MR after bone marrow transplantation in two patients with metachromatic leukodystrophy

Two children with metachromatic leukodystrophy underwent bone marrow transplantation. In both patients MR subsequently showed, first, white matter changes, then later, lack of change as the patients stabilized clinically.

Adrenoleukodystrophy: a scoring method for brain MR observations

PURPOSE

To develop a scoring method for brain observations in patients with X-linked adrenoleukodystrophy.

METHODS

One hundred seventy-five brain MR scans in 83 male subjects less than 20 years of age with proved biochemical defects were reviewed. A severity score (0 to 34), based on a point system derived from location and extent of disease and the presence of focal and/or global atrophy, was calculated for each exam.

RESULTS

Fifty-five of the 83 patients showed MR findings consistent with adrenoleukodystrophy. Two major patterns were observed. A posterior pattern (mean score, 9; range, 0.5 to 25) was present in 80% of patients, and an anterior pattern (mean score, 10; range, 2 to 18) was present in 15% of patients. Serial MR imaging, positive for adrenoleukodystrophy in 34 patients (mean follow-up, 23 months; range, 2 months to 6 years 11 months), showed progressive disease in 52%, progressive disease with subsequent stabilization in 18%, stable disease in 24%, and minimal improvement in 6%.

CONCLUSION

The adrenoleukodystrophy MR severity scoring method is a measure that can be used with standard MR images. When used in conjunction with clinical parameters, this scoring method may help define better the natural history of adrenoleukodystrophy and monitor response to developing therapies.

Childhood cerebral form of adrenoleukodystrophy: short-term effect of bone marrow transplantation on brain MR observations

PURPOSE

To report the serial brain MR observations in patients with childhood-onset cerebral adrenoleukodystrophy 1 to 2 years after bone marrow transplantation.

METHODS

Eight boys with childhood-onset cerebral adrenoleukodystrophy have undergone successful transplantation at our institution. Seven patients (mean age, 8 years 10 months; range, 5 years 3 months to 11 years 9 months) had serial MR studies before and after transplantation. An MR severity score (0 to 34) based on disease location and the presence or absence of focal atrophy was calculated for each patient scan.

RESULTS

Posttransplantation serial MR showed improvement in two patients, stabilization in three patients, and worsening of MR signal changes in two patients. The patient with the most striking progression had systemic graft-versus-host disease. Although the adrenoleukodystrophy MR severity score did not change in three patients after transplantation, two of these patients did show improved margination of disease.

CONCLUSION

Bone marrow transplantation can affect brain MR observations in childhood-onset cerebral adrenoleukodystrophy. Although brain MR findings do not typically resolve, they do seem to stabilize, which is an improvement over the natural MR history of the disease.

CSF findings in adrenoleukodystrophy: correlation between measures of cytokines, IgG production, and disease severity

The childhood-onset cerebral form of adrenoleukodystrophy has a devastating neurologic prognosis. Unfortunately, there is no early method of distinguishing it from the more benign forms of adrenoleukodystrophy, such as adrenomyeloneuropathy. To evaluate the manner in which this disease entity may be reflected in the cerebrospinal fluid, we studied a consecutive series of 19 patients, all with biochemically proved adrenoleukodystrophy. total protein, immunoglobulin production, cytokine levels, and cerebrospinal fluid pressure were measured. In this single sample of cerebrospinal fluid, a significant correlation existed between clinical stage of the illness and cerebrospinal fluid myelin basic protein. No correlation existed with total protein, cytokines, or measures of immunoglobulin production.

Dense peripheral corneal clouding in Scheie syndrome

A 28-year-old woman with Scheie syndrome (MPS I-S) presented with the unusual feature of extremely dense peripheral corneal clouding, allowing maintenance of good central visual acuity. Characteristic systemic features, an abnormal electroretinogram result, and absent alpha-L-iduronidase activity confirmed the diagnosis despite the unusual corneal pattern of clouding.

Characteristics of the dementia in late-onset metachromatic leukodystrophy

Patients with metachromatic leukodystrophy (MLD) of juvenile or adult onset present with behavioral abnormalities. In nine patients, diagnosed between ages 11 and 33 years, behavior and neuropsychological test results disclosed a pattern of dementia combining features associated with both frontal and white matter abnormalities. All the patients had been considered to have a psychiatric disorder prior to the diagnosis of MLD, even though none had any of the cardinal features of schizophrenia or other major psychosis. Early diagnosis of late-onset MLD is important to provide access to appropriate effective therapy.

Light and electron microscopic features of the liver in mucopolysaccharidosis

The mucopolysaccharidosis (MPS) diseases lead to the accumulation of glycosaminoglycan in many tissues. In this study 19 MPS I, one MPS II, five MPS III, and two MPS VI patients underwent liver biopsy for light and electron microscopic examination. Electron microscopy was performed for all 27 specimens. Twenty-six specimens were studied by light microscopy, and the slides were stained with colloidal iron and alcian blue in 26 and six biopsy specimens, respectively. By hematoxylin-eosin stain 20 of 26 cases showed hepatocellular dilatation with rarefaction of the cytoplasm; the Kupffer cells were unremarkable. Twenty-four and 25 of the 26 biopsy specimens showed substantial colloidal iron staining of hepatocytes and Kupffer cells, respectively. The six biopsy specimens prepared with alcian blue stain showed no reactivity of any cell type. Electron microscopy revealed characteristic membrane-bound inclusions within the hepatocytes and Kupffer cells of all 27 biopsy specimens. Of 19 cases in which Ito cells were identified, 18 included cells containing similar inclusions. Twenty of 27 biopsy specimens also demonstrated the hepatocellular accumulation of lipid droplets. Although there were no absolute distinguishing features among the various MPS diseases, the two MPS VI cases showed glycosaminoglycan inclusions that were fewer in number, smaller, and contained more abundant lipofusion than those associated with the other MPS types.

Male donor-derived cells in the brains of female sex-mismatched bone marrow transplant recipients: a Y-chromosome specific in situ hybridization study

In five female bone marrow transplant (BMT) recipients of sex-mismatched donor marrow, Y-chromosome specific in situ hybridization was performed on formalin-fixed, paraffin-embedded sections of the medulla to detect the male donor marrow-derived cells. Y-chromosome-bearing cells (Y-cells), thereby donor-derived, were matched with leukocyte common antigen (LCA)-reactive cells in adjacent sections immunostained with anti-LCA antibody. Y-cells included mononuclear leukocytes (MNL) within the vessel lumen and infiltrating the perivascular space and parenchyma, and "perivascular cells." We have, therefore, concluded that donor marrow-derived MNL, though limited in number, do enter the normal-appearing brain and can transform to "perivascular cells" in human BMT recipients. It remains, however, to be confirmed whether MNL entering the normal adult CNS parenchyma transform to ramified microglia.

Children with mucopolysaccharidosis: perioperative care, morbidity, mortality, and new findings

The perioperative care, morbidity, and mortality in 30 patients with mucopolysaccharidosis (MPS) are presented. They underwent a detailed preoperative assessment and were anesthetized 141 times. An intravenous induction technique was used in most patients. It was easier to see the vocal cords, during laryngoscopy, in children with Hurler syndrome (HS) when they were younger (23 v 41 months, P < or = .01) and smaller (12 v 15 kg, P < or = .05). Preoperative obstructive breathing was associated with a significantly higher incidence of postextubation obstruction (P < or = .05). A total of 28 children underwent bone marrow transplantation (BMT); this reversed upper airway obstruction and also reversed intracranial hypertension. In children with HS, the incidence of odontoid dysplasia was 94%; 38% demonstrated anterior C1-C2 subluxation. Head and neck manipulation was limited in children with cervical spine defects. None of the 30 patients experienced spinal cord morbidity. One child suffered an intraoperative stroke; another, pulmonary edema. Severe and extensive coronary obstruction was responsible for 2 intraoperative deaths. Coronary angiography underestimated coronary artery disease.