Case files of the New York City poison control center: paradichlorobenzene-induced leukoencephalopathy

Spongiform leukoencephalopathy: A unique case of biopsy confirmed leukoencephalopathy secondary to toxic, non-inflammatory exposure

Toxin-induced leukoencephalopathy is a rare neurological condition that has been previously associated with intracranial radiation, chemotherapy, drugs of abuse, and environmental exposures. Herein, we present a patient with brain-biopsy proven toxin-induced leukoencephalopathy, likely secondary to multiple environmental offenders including insecticides and non-Food and Drug Administration approved anabolic steroids, opioids, and benzodiazepines. A 60-year-old man presented to our service as a direct transfer from an outside facility for evaluation of a rapidly progressive neuropsychiatric decline. Extensive workup with blood work, cerebrospinal fluid analysis, paraneoplastic panel, serial magnetic resonance imaging brain with and without contrast, and electroencephalograms were unrevealing. Magnetic resonance imaging brain showed diffuse confluent white matter disease, which was non-specific. The patient was treated with high-dose methylprednisolone and trials of intravenous immunoglobulin without any significant improvement. Finally, a brain biopsy was performed, and pathology confirmed a spongiform leukoencephalopathy, favoring a toxin-related etiology. The diagnosis of toxin-induced leukoencephalopathy should be considered in patients with steep neuropsychiatric decline and associated diffuse white matter disease. Diagnosis relies heavily on history of exposure, clinical presentation, imaging findings, and ultimately, histopathology from brain biopsy. The recognition of the clinical presentation is important to pursue the appropriate diagnostic workup and treatment.

PDCB does not promote CNS autoimmunity in the context of genetic susceptibility but worsens its outcome

BACKGROUND

Para-dichlorobenzene (PDCB) is an aromatic hydrocarbon contained in mothballs that is potentially neurotoxic. A potential pathogenic role of PDCB in MS pathogenesis has been suggested.

METHODS

To determine the ability of chronic PDCB ingestion to induce CNS autoimmunity in a genetically susceptible mammalian species, naive myelin oligodendrocyte glycoprotein peptide (MOG_p)35-55 T cell receptor (TCR) transgenic mice (2D2) on the C57Bl/6 background were orally gavaged once daily with corn oil control, 125 mg/kg PDCB, or 250 mg/kg PDCB for 45 days. The incidence of spontaneous EAE is increased in this mouse strain.

RESULTS

Both PDCB treatment groups showed the same spontaneous incidence of EAE, an earlier disease onset, and a slight decrease in survival for 125 mg/kg PDCB mice compared to control mice. We were unable to detect any PDCB, or its metabolites 2,5-dichlorophenol, 2,5-dicholormethylsulfide, and 2,5-dichloromethylsulfone in the brain and spinal cord of control mice. In contrast, PDCB was readily detectable in both compartments in mice who received PDCB via oral gavage, with concentrations being significantly higher in the brain (p < 0.01). Levels of the metabolites 2,5-dichlorophenol and 2,5-dichloromethylsulfone were also significantly higher in brains compared to spinal cords.

CONCLUSION

Our study refutes the hypothesis that PDCB or its metabolites trigger spontaneous T cell-mediated CNS autoimmunity in the setting of genetic susceptibility. A slight increase in mortality with PDCB exposure may be due systemic toxicity of hydrocarbons.

Toxic Leukoencephalopathy in the Intensive Care Unit

In this article, we report two cases of acute toxic leukoencephalopathy to highlight this acute clinicoradiological syndrome as an important, although uncommon, consideration in the undifferentiated comatose patient who fails to wake following drug overdose or has unexplained neurology with a history of drug exposure. We then review the current literature and discuss potential differential diagnoses in this setting, along with proposed treatments for this condition. The cases presented demonstrate a more fulminant onset than previously well-defined acute toxic leukoencephalopathy subtypes and highlight the prognostic importance of magnetic resonance imaging in diagnosing a condition from which significant functional recovery seems possible.

Para-dichlorobenzene toxicity - a review of potential neurotoxic manifestations

BACKGROUND

Para-dichlorobenzene (PDCB) is an active ingredient of mothballs, deodorizers and fumigants. Due to the easy availability of this chemical, there is a considerable risk for accidental or intentional toxic exposure. Recently, multiple cases of PDCB toxicity due to mothball ingestion were reported. PDCB toxicity can affect multiple organ systems including liver, kidneys, skin, lung and the central nervous system (CNS). CNS toxicity often results in leukoencephalopathy and heterogeneous neurological manifestations.

OBJECTIVES

The objective of this study was to illustrate the clinical presentation, imaging findings, diagnosis and management of PDCB toxicity.

METHODS

We carried out a literature review of the pharmacological and toxicological properties of PDCB.

CONCLUSIONS

PDCB and other aromatic hydrocarbons are capable of CNS tissue damage and in promoting functional neurological decline. While very little is currently known about prevalence of PDCB addiction, it cannot be ruled out that its illicit use among young people is under-recognized. The number of cases of PDCB toxicity might also rise due to the increasing industrial and domestic use of this chemical.

A Case of Reversible Neuropsychiatry Symptoms in HIV due to Toxic Leukoencephalopathy

Mothball ingestion has been previously cited to induce toxic-leukoencephalopathy, secondary to the destructive effects of paradichlorobenzene on central nervous system white matter. This case presents a 37-year-old woman who experienced a neuropsychiatric syndrome consistent with paradichlorobenzene-induced toxic leukoencephalopathy after two decades of mothball abuse. Her clinical presentation was insidious, involving fluctuating cognitive decline, depression, and psychosis. This was further complicated by an human immunodeficiency virus infection and concomitant cocaine abuse. Ultimately, her clinical findings were attributed to a reversible toxic-leukoencephalopathy from mothball ingestion, and her magnetic resonance imaging findings were consistent with symmetric leukoencephalopathy and atrophy. Though leukoencephalopathy in human immunodeficiency virus has numerous potential etiologies, a patient with a history of substance abuse warrants consideration of toxin-induced leukoencephalopathy, and further inquiry regarding abuse of other substances is appropriate.

Paradichlorobenzene (toxin)-induced leucoencephalopathy

A 40-year-old woman with a history of polysubstance abuse, hypertension, depression and anxiety with panic attacks admitted to the emergency room at the request of her primary physician owing to progressive decline in her mental status associated with anorexia and generalised pruritic skin rashes. Initial outpatient workup and that during two previous hospital admissions including thyroid function and syphilis tests, urine toxicology screen and brain imaging studies were unremarkable. Repeat MRI of the brain during her third hospital admission showed diffuse periventricular and white matter disease. This prompted further questioning of family members which revealed chronic ingestion of mothballs and toilet cakes containing paradichlorobenzene in the patient leading to toxin-induced leucoencephalopathy consistent with her neurological symptoms of altered mental status, ataxic gait, cogwheel rigidity in the arms and characteristic skin rashes. Subsequently, a feeding tube was placed to address her worsening nutritional status and she was discharged home in a stable state.