Mitoxantrone-related acute leukemia in two MS patients

We report two new cases of mitoxantrone-related leukemia occurring in two patients with multiple sclerosis (MS), 14 and 18 months after the last infusion of the drug. One patient was successfully treated. We were able to collect 29 other cases in the literature. Most of them were single reports but some were described within cohorts of mitoxantrone-treated MS patients. The incidence rate was 0.65% from all cohorts totalizing 2299 patients. Acute promyelocytic leukemia with the translocation t(15;17) was over-represented in the MS population in comparison with cancer patients also treated with mitoxanrone. The occurrence of leukemia was dose-independent and appeared with a mean delay of 20 months after the end of the treatment.

Polymerase chain reaction analysis and oligoclonal antibody in the cerebrospinal fluid from 34 patients with varicella-zoster virus infection of the nervous system

OBJECTIVE

To study cerebrospinal fluid (CSF) and serum samples from 34 consecutive patients suspected of having varicella-zoster virus (VZV) infection of the central nervous system (CNS).

POPULATION AND METHODS

The patients were divided into three groups. The first group consisted of 27 patients with a rash in one to three dermatomes and clinical suspicion of meningitis and radiculitis; among them, three subgroups were distinguished according to the affected dermatome: ophthalmicus (n = 9), oticus (n = 11) and cervico-thoraco-lumbar zoster (n = 7). Four cases of zoster sine herpete (ZSH) were included in the second group: these patients presented with either radiculitis (n = 2) or meningoencephalitis (n = 2), without cutaneous eruption. The third group consisted of three patients with a generalised rash and encephalitis. A polymerase chain reaction (PCR) for VZV DNA and antigen-driven immunoblots for oligoclonal anti-VZV antibodies were carried out on all CSF samples.

RESULTS

PCR of the CSF was positive in 44% of the patients from the first group, mainly within the first 7 days after eruption. In addition, intrathecal synthesis of anti-VZV antibodies was detected in 37% of patients, always after an interval of 7 days (p<0.0001). Among the four patients with ZSH, a positive VZV PCR was detected in three patients and CSF-specific oligoclonal anti-VZV antibodies in two. PCR was also positive in the CSF of two of the three patients with generalised rash and encephalitis; local production of anti-VZV antibodies was seen in a second CSF sample in one patient, and was also present in the third patient.

CONCLUSION

Amplification of VZV DNA by PCR in the CSF and antigen-driven immunoblots have important diagnostic value in suspected VZV infection, although their presence depends on the timing of the CSF sampling. VZV is thought to be a causative agent in unexplained cases of meningitis associated with radiculitis or focal CNS symptoms, even in the absence of skin manifestations. In such patients, rapid diagnosis by this combined approach permits early antiviral treatment.

Detection of oligoclonal free kappa chains in the absence of oligoclonal IgG in the CSF of patients with suspected multiple sclerosis

BACKGROUND

Oligoclonal free kappa bands are present as frequently as oligoclonal IgG bands in the cerebrospinal fluid (CSF) from patients with definite multiple sclerosis (MS) and can even occur in the absence of oligoclonal IgG. As such, they too are markers of an ongoing intrathecal immune process.

OBJECTIVES

To determine how frequently oligoclonal free kappa bands are detectable in the CSF from patients with clinical signs and symptoms suggestive of MS in the absence of CSF restricted oligoclonal IgG.

METHODS

An immunoaffinity mediated immunoblotting technique specific for free kappa chains was used, after isoelectric focusing of paired CSF and serum samples from 33 patients with clinical signs and symptoms suggestive of MS but without CSF oligoclonal IgG. CSF data were correlated with MRI results in the context of the new diagnostic criteria from McDonald et al.

RESULTS

Eighteen CSF samples contained oligoclonal free kappa bands (54%), mainly from patients with motor dysfunction (83%) and optic neuritis (64%). All patients with a positive MRI according to Barkhof's criteria (n = 6) had free kappa bands in their CSF.

CONCLUSIONS

(1) Oligoclonal free kappa bands in the CSF are related to the dissemination of MS lesions; (2) such bands should be looked for in oligoclonal IgG negative CSF, and (3) the presence of free kappa bands in the CSF may be a substitute for oligoclonal IgG in the McDonald's criteria for diagnosis of MS.

Clinical relevance of polymerase chain reaction (PCR) assays and antigen-driven immunoblots for the diagnosis of neurological infectious diseases

Polymerase chain reaction assays are a powerful tool for detecting the presence of infectious genomes in the cerebrospinal fluid. Positive results always mean a current or pending infection of the central nervous system. Subacute (>7 days) or chronic infections induce an intrathecal humoral immune response and the appearance of oligoclonal IgG antibodies directed against the causal infectious agent. This local synthesis may be observed even in cases of severe systemic immunodeficiency. The use of polymerase chain reactions in combination with the detection of a specific intrathecal immune response should represent the most reliable strategy for the diagnosis of viral and chronic infections of the central nervous system. The authors describe their experience, using this approach, in herpetic encephalitis, acute and recurrent herpetic meningitis, varicella zoster-induced neurological diseases, cytomegalovirus encephalitis, progressive multifocal leukoencephalitis and tuberculous meningitis.

The intrathecal humoral immune response: laboratory analysis and clinical relevance

In normal conditions, albumin and immunoglobulin (Ig)G in the cerebrospinal fluid (CSF) originate from the blood, and there is no antibody production within the central nervous system. Up to 20% of CSF proteins are intrathecally synthesized, but the major fraction is blood-derived. The CSF/serum albumin quotient (QAlb) is the best marker of the blood-CSF barrier function. The corresponding immunoglobulin quotients (QIGG, QIGA, QIGM) are not linearly related to QAlb and their correlations are defined by an hyperbolic equation. This equation is used to discriminate between a blood-derived and a locally produced fraction of immunoglobulins in case of an intrathecal humoral immune response. The detection of CSF-specific oligoclonal IgG is more sensitive than the quantitative comparison between QIGG and QAlb. A further step is the determination of antibody indices and the detection of specific oligoclonal antibodies by antigen-driven immunoblots. CSF analysis remains a cornerstone for the diagnosis of various neurological disorders, including multiple sclerosis and infectious diseases of the central nervous system.

Eosinophilic pleocytosis and myelitis related to Toxocara canis infection

Toxocara canis causes the visceral larva migrans syndrome in which central nervous involvement is rare. We report the case of a 40-year-old woman presenting with a subacute weakness of the right leg and dysaesthesiae in the right Th8-Th10 dermatomas. Spinal magnetic resonance imaging examination showed abnormal hyperintensity within the spinal cord. Cerebrospinal fluid analysis revealed eosinophilic pleocytosis. Antibody titres to Toxocara canis were higher in the cerebrospinal fluid than in the serum. Treatment using mebendazole led to a complete clinical recovery, normalization of cerebrospinal fluid parameters and improvement in spinal magnetic resonance imaging abnormalities.

Clinical relevance of the determination of anti-GQ1b antibodies in Miller Fisher and Guillain-Barré syndromes

Anti-GQ1b antibodies were assayed by an enzyme-linked immunosorbent assay in sera from patients with non-neurological disorders (N = 20), and with various neurological disorders (N = 59), including nine cases of Miller Fisher syndrome, 16 cases of Guillain-Barré syndrome and one case of acute post-infectious ophthalmoparesis. Such antibodies were found in most cases (8 out of 9) of Miller Fisher syndrome, and at very high titres, in one case of Guillain-Barré syndrome characterised by an initial ophthalmoparesis, and in the case of isolated post-infectious ophthalmoparesis. The latter was characterised by a long-lasting occurrence of these antibodies. Anti-GQ1b antibodies are specific for an immune-mediated neuropathy of the cranial, especially oculomotor, nerves.