Pyridoxine and pyridostigmine treatment in vincristine-induced neuropathy

Novel management of critically induced polyneuropathy in intensive care patients: A case report of two patients

There has been tremendous growth in patients requiring critical care with severe infections. During a prolonged stay in the intensive care unit (ICU), patients develop critical illness polyneuropathy (CIP). The early identification of neurological involvement requires special attention during ICU care. We describe two cases who developed complete motor weakness after a prolonged stay in ICU. Patients were successfully managed with pyridostigmine and testosterone hormonal therapy initially and later with pyridostigmine only. The present case series highlights the need for early recognition, assessment, and novel management of CIP in ICU patients. However, the role of nutrition, physiotherapy, and supportive care is equally essential for the successful outcome in these patients.

Effect of pyridoxine plus pyridostigmine treatment on vincristine-induced peripheral neuropathy in pediatric patients with acute lymphoblastic leukemia: a single-center experience

BACKGROUND

Vincristine (VCR), which is a key component of chemotherapy, is important for survival. VCR is associated with a well-known side effect, including neurotoxicity.

AIMS

The aim of this study was to evaluate the features of vincristine-induced peripheral neuropathy (VIPN) and the effectiveness of pyridoxine plus pyridostigmine therapy in children with acute lymphoblastic leukemia.

METHODS

The WHO and NCI CTCAE neurotoxicity scorings were used to evaluate VIPN at diagnosis, in the first month, and after the third month of the treatment. The clinical features of 23 patients having acute lymphoblastic leukemia with VIPN during the period of July 2013-February 2016 were prospectively evaluated.

RESULTS

The mean age was 72.8 ± 51.6 months, and 26.1%, 56.5%, and 17.4% were in standard, moderate, and high-risk groups, respectively. Neuropathy frequently occurred at induction (82.6%) and reinduction (17.4%) of the protocol. Drop foot (82.6%), leg pain (82.6%), and difficulty in walking (82.6%) were observed. The mean total cumulative dose of neuropathy occurrence was 5.6 ± 2.03 mg/m². Our study showed that both the WHO and NCI CTCAE scorings were significantly improved via pyridoxine plus pyridostigmine therapy.

CONCLUSION

The WHO and NCI CTCAE scorings may be used for evaluating neuropathy at diagnosis and follow-up of neurotoxicity with treatment. Pyridoxine plus pyridostigmine therapy may be an effective option in the treatment of VIPN.

Nutrition during childhood cancer treatment: current understanding and a path for future research

Proper nutritional status during cancer therapy has been recognised as being integral to a variety of health outcome measures, including overall survival, treatment tolerance, and quality of life. The prevalence of malnutrition, defined by WHO as either undernutrition or overnutrition, among children and adolescents with cancer is reported to be as high as 75%. Yet, over the past two decades there have been limited advances in elucidating the underlying pathophysiological drivers of malnutrition in this population. This effect has resulted in a paucity of research aimed at improving nutritional assessment and intervention among this group. This Review presents an in-depth discussion of the role of nutritional status in paediatric cancer care, as well as evolving avenues of investigation that might propel personalised nutrition into a viable reality. Thus, nutritional science might facilitate individualised intervention strategies, and thereby help to optimise clinical outcomes for patients and survivors of childhood cancer.

Role of pyridoxine in GABA synthesis and degradation in the hippocampus

Pyridoxal-5'-phosphate, the active form of vitamin B₆, is associated with activities of several enzymes and the treatment of various neurological disorders. Here, we investigated the effects of pyridoxine on the immunoreactivity and protein levels of γ-aminobutyric acid (GABA)-synthesizing and degradation enzymes such as glutamic acid decarboxylase (GAD), GABA transaminase (GABA-T), and succinic semialdehyde dehydrogenase (SSADH), in the hippocampus of mice. The mice intraperitonially received physiological saline and 350 mg/kg pyridoxine, twice a day for 21 days, and were euthanized 2 h after the final dose. In the vehicle-treated group, we observed GAD67 immunoreactivity in the stratum pyramidale of the CA1 and CA3 region, Schaffer collateral, polymorphic layer, and outer granule cell layer of the dentate gyrus. Pyridoxine administration significantly increased GAD67 immunoreactivity, while significantly decreasing GABA-T immunoreactivity in pyridoxine-treated mouse hippocampi (CA1 region and dentate gyrus). In the stratum lacunosum-moleculare of CA1 region, GABA-T immunoreactivity was significantly increased in the pyridoxine-treated group compared to that in the vehicle-treated group, although GAD67 immunoreactivity was similarly observed in these groups. Alternatively, there were no significant differences in SSADH immunoreactivity in any regions of the hippocampus between the vehicle- and pyridoxine-treated groups. Western blot analysis showed significant increases in GAD67 and GABA-T protein levels in the pyridoxine-treated group compared with those in the vehicle-treated group. Therefore, pyridoxine administration facilitates GABA turnover in mouse hippocampus by modulating the GABA-synthesizing and degradation enzymes.

Neurological Complications of Pediatric Cancer

Neurologists are often consulted for diagnosis and management of neurologic complications in patients undergoing therapy for cancer. Pediatric patients with cancer, often undergoing the same types of therapy as adults with cancer, may experience different adverse events. The set of neurologic complications in children differs from that in adults and the neurologist must take into account the continuing growth and development of the patient as well as significant differences in primary diagnosis across the population. Correctly recognizing complications and initiating prompt treatment may reduce pain and prevent further progression and permanent deficits. Herein, we review the most recent literature on the neurological complications of cancer therapy organized by frequency in the pediatric population.

Vincristine-Induced Neuropathy Presenting as Ptosis and Ophthalmoplegia in a 2-Year-Old Boy

Vincristine is used in the treatment of leukemias, solid tumors, and lymphomas. A case of a 2-year-old boy undergoing treatment for leukemia who developed sudden onset bilateral ptosis and ophthalmoplegia along with generalized neuropathy due to vincristine's neurotoxic effects is presented. He was successfully treated with pyridoxine and pyridostigmine. The possible mechanisms of action and the treatment for vincristine-induced neuropathy are discussed. Prompt treatment and close follow-up is needed, especially in children because prolonged ptosis and motility restriction may have a profound effect on a child's visual function.

Vincristine-induced polyneuropathy in a child with stage I Wilms' tumour presenting with unilateral abducens nerve palsy

A 4-year-old boy presented with right esotropia while receiving vincristine and dactinomycin for stage I Wilms' tumour according to the National Wilms Tumour Study-5 protocol. On examination, he had isolated limitation of his right lateral gaze. CT of the brain and cerebrospinal fluid examination were normal. A nerve conduction velocity study which was performed on the peripheral nerves revealed predominant motor polyneuropathy compatible with axonal loss involving the upper limbs. The patient had received a cumulative vincristine dose of 17 mg/m(2) before developing esotropia. Vincristine-induced abducens nerve mononeuropathy and subclinical motor polyneuropathy was suspected. Unilateral esotropia markedly improved after the discontinuation of vincristine and a short course of oral pyridoxine treatment.

[Vincristine-induced unilateral ptosis: case report and review of the literature]

We report the case of a 31-month-old girl, treated by the ifosfamide-vincristine-actinomycin chemotherapy protocol for vaginal rhabdomyosarcoma, who developed a unilateral left ptosis on day 36 of chemotherapy, i.e. 7 days after the fifth vincristine dose (1.5mg/m(2) or 0.90 mg). The cumulative vincristine dose was thus 4.50mg. The remainder of the neurological and systemic examinations were unremarkable. Laboratory testing and thoracic-cervical-cranial CT were normal. Other causes of ptosis were excluded. The ptosis decreased a few days after the infusion of vincristine and re-increased just after a new dose. It finally resolved upon lowering the dose of vincristine. According to our observations, the role of vincristine in the pathogenesis of this ptosis appears "likely". In such cases, maintenance of treatment is possible with adjustment of vincristine doses, but requires regular follow-up.

Chemotherapy-Induced Peripheral Neuropathy in Pediatric Cancer Patients

Chemotherapy-induced peripheral neuropathies (CIPNs) are an increasingly common neuropathic and pain syndrome in adult and pediatric cancer patients and survivors [1-69]. However, symptoms associated with CIPNs are often undiagnosed, under-assessed, and communications problems between clinicians, family members, and patients have been observed [70-73]. Less is known about the prevalence and impact of CIPNs on pediatric cancer populations [70-71]. This article aims to provide a brief understanding of CIPNs in pediatric populations, and to review the evidence for both its prevention and treatment.

Successful treatment of vincristine induced ptosis and polyneuropathy with pyridoxine and pyridostigmine in a child with acute lymphoblastic leukemia

Vincristine is used in the treatment of solid tumors, lymphoma and leukemia in children. The dose-limiting toxicity is its neurotoxicity. We describe a 2-year-old girl with acute lymphoblastic leukemia who developed vincristine-induced polyneuropathy with bilateral ptosis and recovered on treatment with pyridoxine and pyridostigmine.

Pyridoxine enhances cell proliferation and neuroblast differentiation by upregulating the GABAergic system in the mouse dentate gyrus

We investigated the effects of pyridoxine (vitamin B(6)) on cell death, cell proliferation, neuroblast differentiation, and the GABAergic system in the mouse dentate gyrus. We administered pyridoxine (350 mg/kg intraperitoneally) to 8 week old mice twice a day for 14 days and sacrificed them at 10 weeks of age. Pyridoxine treatment did not induce neuronal death or activate microglia in the dentate gyrus, while glial fibrillary acidic protein (GFAP)-positive cells were significantly increased in the subgranular zone of the dentate gyrus. The increase in GFAP-positive cells was confirmed to be due to proliferating cells based on double immunofluorescence staining. GFAP-positive cells, which were also labeled with Ki67, a marker for cell proliferation, and doublecortin, a marker for neuroblast differentiation, were significantly increased in the pyridoxine-treated group compared to those in the vehicle-treated group. Pyridoxine treatment also increased the protein levels of glutamic acid decarboxylase (GAD) 67, an enzyme for GABA synthesis, and pyridoxal 5'-phosphate (PNP) oxidase, an enzyme for pyridoxal phosphate synthesis, in the dentate gyrus. These results suggest that pyridoxine treatment distinctly increases cell proliferation, neuroblast differentiation, and upregulated the GABAergic system, as revealed by the increases of GAD67 and PNP oxidase in the mouse dentate gyrus.

A trial to assess the efficacy of glutamic acid in prevention of vincristine-induced neurotoxicity in pediatric malignancies: a pilot study

Vincristine is considered as a backbone of therapy in the induction and consolidation phases of pediatric malignancies. Neurotoxicity is a principal side effect of its use. This study is a randomized single-blinded placebo-controlled clinical trial to evaluate the role of glutamic acid in ameliorating neurotoxicity in pediatric patients with hematologic and solid tumors receiving vincristine during induction course. Fifty-four patients in the glutamic acid group received glutamic acid 1.5 grams daily orally in 3 divided doses during the 4-week induction with vincristine in a dose of 1.5 mg/m² IV weekly. Placebo group (40 patients) received oral placebo 3 times daily in the same way as the glutamic acid group. The onset of neurotoxicity was significantly earlier in placebo group than in glutamic acid group regarding tendon Achilles reflex, Patellar reflex, parasthesia, and increased frequency of constipation. This was statistically significant mostly in third and fourth visits, no severe cases of strength and mental alteration side effects in both groups. Glutamic acid was well tolerated with no gastrointestinal side effects in patients. This study suggests that the coadministration of oral glutamic acid with repetitive intravenous bolus injections of vincristine resulted in a reduction of its neurotoxicity.

Use of pyridoxine and pyridostigmine in children with vincristine-induced neuropathy

Four children with vincristine (VCR)-induced neuropathy are being reported. All cases were followed with the diagnosis of acute lymphoblastic leukemia. Two were boys aged between 2 and 13 year. Electromyographic examination consisted of sensoriomotor polyneuropathy with axonal involvement in three patients. In another patient, it consisted of motor axonal polyneuropathy. In all patients, pyridoxine and pyridostigmine were successfully used in the treatment of VCR-induced neuropathy. They recovered completely with this drug combination. Recovering period of symptoms was between 1-2 week.

Vincristine-induced peripheral neuropathy in a neonate with congenital acute lymphoblastic leukemia

We report the case of a 46-day-old boy with a fulminant vincristine-induced peripheral neuropathy after treatment for congenital acute lymphoblastic leukemia. Flaccid paralysis developed at the end of the first phase of induction, requiring intubation and ventilation for 51 days. Treatment was initiated with levocarnitine, N-acetylcysteine, and pyridoxine and progressive reversal of the neuropathy occurred over the next 4 months. Potential differences in pathogenesis and presentation of vincristine neurotoxicity and Guillian-Barre syndrome in the neonate are discussed.

A comparison of acute lymphoblastic leukemia in Down syndrome and non-Down syndrome children: the role of trisomy 21

Down syndrome (DS), which occurs once in every 800 births, is associated with a trisomy on locus 21. Among the many aberrations caused by DS, including shortened stature and distorted facies, are several blood dyscrasias, including childhood leukemias-namely, acute myeloid leukemia (AML) and acute lymphoblastic, or lymphocytic, leukemia (ALL). One focus of the diagnosis of ALL is to distinguish it from AML.The benefits of immunophenotyping extend to treatment as well. ALL is associated with an inherited trisomy 21 in DS children (ALL-DS) and with acquired trisomies, +21, 8, and 13, in non-DS children (ALL-NDS). The differences in treatment, outcome, and prognosis between ALL-DS and ALL-NDS can be attributed to the interaction of their respective trisomies with several genetic mutations, including one on the GATA1 growth factor transcription gene. Other mutations are the gene fusion at TEL/AML1, and a new mutation found, which labels the Janus Kinase gene or JAK2 as on oncogenic precursor, which when associated with the B-cell precursor gene or BCP is highly leukomogenic. The treatments for the 2 groups have been based on quality of risk, with ALL-DS children having the highest risk along with the poorest prognosis, but alterations in medication regimens have brought treatment outcomes to near equality. It is worthwhile to study the trisomy 21 because in the future it may provide an understanding of all blood dyscrasias.

Clinical challenges associated with bortezomib therapy in multiple myeloma and Waldenströms Macroglobulinemia

Rapid development of the small molecule proteasome inhibitor bortezomib has yielded important clinical benefit for patients with multiple myeloma. Early phase clinical trials suggest the agent has similar efficacy in Waldenströms Macroglobulinemia. Optimization of bortezomib-based therapy, though, requires an understanding of the various challenges associated with use of the drug. This review highlights the rationale for bortezomib therapy in patients with multiple myeloma and Waldenströms Macroglobulinemia, mechanisms of bortezomib resistance, important therapy-related side effects, and new directions for the use of proteasome inhibitors in these disorders.