Reversible stiff person syndrome presenting as an initial symptom in a patient with colon adenocarcinoma

Isolation and identification of flavonoid-producing endophytic fungi from medicinal plant Conyza blinii H.Lév that exhibit higher antioxidant and antibacterial activities

Background

Conyza blinii H. Lév is a medicinal plant that has a variety of pharmacological activities, but its study is at a standstill due to the shortage of resources.

Method

This study utilized the surface sterilization method to isolate endophytic fungi, and they were preliminarily identified by morphology. Flavonoid-producing strains were screened by NaNO₂-Al(NO)₃ colorimetry and further identified by the ITS sequence. Additionally, we used five antioxidant assays (DPPH, Hydroxyl radical, ABTS, FRAP and T-AOC assays) to systematically evaluate the antioxidant capacity of total flavonoids , and we also determined their antibacterial activity.

Results

In this study, 21 endophytic fungi were isolated from wild Conyza blinii H. Lév for the first time. There were six flavonoid-producing strains, especially CBL11, whose total flavonoid content reached 50.78 ± 2.4 mg/L. CBL12, CBL12-2 and CBL1-1 all exhibited excellent antioxidant activity. The effect of CBL12 was similar to that of ascorbic acid at low concentrations, and its radical scavenging rates for DPPH and ABTS were 94.56 ± 0.29 % and 99.88 ± 0.27%, respectively, while its IC₅₀ values were only 0.11 ± 0.01 mg/mL and 0.2 ± 0.01 mg/mL. Through LC-MS, we found that CBL12 could produce many high-value flavonoids, such as 3-methoxyflavone, nobiletin, formononetin, scopoletin, and daidzein. Additionally, CBL9 had good antibacterial activity against both gram-positive and gram-negative bacteria. Notably, we obtained the high-yield strains CBL12 and CBL9, which not only had high yields (10.64 ± 1.01 mg/L and 10.17 ± 0.11 mg/L, respectively) but also had excellent biological activity. Hence, the results of this study provide new ideas for endophytic fungi that can be exploited as a source of flavonoids and other medicinal components from Conyza blinii H. Lév. Moreover, this study can serve as a reference for the development of rare medicinal materials.

GAD65 neurological autoimmunity

The glutamic acid decarboxylase 65-kilodalton isoform (GAD65) antibody is a biomarker of autoimmune central nervous system (CNS) disorders and, more commonly, nonneurological autoimmune diseases. Type 1 diabetes, autoimmune thyroid disease, and pernicious anemia are the most frequent GAD65 autoimmune associations. One or more of these disorders coexists in approximately 70% of patients with GAD65 neurological autoimmunity. Neurological phenotypes have CNS localization and include limbic encephalitis, epilepsy, cerebellar ataxia, and stiff-person syndrome (SPS), among others. Classic SPS is a disorder on the spectrum of CNS hyperexcitability which also includes phenotypes that are either more restricted (stiff-limb syndrome) or more widespread (progressive encephalomyelitis with rigidity and myoclonus). GAD65 antibody is not highly predictive of a paraneoplastic cause for neurological disorders, but diverse cancer types have been occasionally reported. For all phenotypes, responses to immunotherapy are variable (approximately 50% improve). GAD65 autoimmunity is important to recognize for both coexisting nonneurological autoimmune associations and potential immunotherapy-response. Muscle Nerve 56: 15-27, 2017.

Autoimmune movement disorders

Autoimmune movement disorders encapsulate a large and diverse group of neurologic disorders occurring either in isolation or accompanying more diffuse autoimmune encephalitic illnesses. The full range of movement phenomena has been described and, as they often occur in adults, many of the presentations can mimic neurodegenerative disorders, such as Huntington disease. Disorders may be ataxic, hypokinetic (parkinsonism), or hyperkinetic (myoclonus, chorea, tics, and other dyskinetic disorders). The autoantibody targets are diverse and include neuronal surface proteins such as leucine-rich, glioma-inactivated 1 (LGI1) and glycine receptors, as well as antibodies (such as intracellular antigens) that are markers of a central nervous system process mediated by CD8+ cytotoxic T cells. However, there are two conditions, stiff-person syndrome (also known as stiff-man syndrome) and progressive encephalomyelitis with rigidity and myoclonus (PERM), that are always autoimmune movement disorders. In some instances (such as Purkinje cell cytoplasmic antibody-1 (PCA-1) autoimmunity), antibodies detected in serum and cerebrospinal fluid can be indicative of a paraneoplastic cause, and may direct the cancer search. In other instances (such as 65kDa isoform of glutamic acid decarboxylase (GAD65) autoimmunity), a paraneoplastic cause is very unlikely, and early treatment with immunotherapy may promote improvement or recovery. Here we describe the different types of movement disorder and the clinical features and antibodies associated with them, and discuss treatment.

The horses are the first thought but one must not forget the zebras even if they are rare: Stiff person syndrome associated with malignant mesothelioma

Stiff person syndrome (SPS) is a rare condition that causes rigidity in the muscles of the body and extremities, difficulty in walking, episodic spasms and progressive disability. SPS is generally seen together with autoimmune disorders such as diabetes mellitus, thyroiditis, vitiligo and pernicious anaemia. Rarely, it may develop as a paraneoplastic condition. SPS cases associated with breast cancer, small cell lung carcinoma, thymoma, Hodgkin's lymphoma and colorectal cancer have been reported in the literature. We present a case of a 58-year-old female patient who had malignant mesothelioma-associated SPS. Patients who have muscle spasms and difficulty in movement of joints should be evaluated for SPS before diagnosis of Parkinson's or other neurological disorders, and possible underlying malignancies should be excluded.

Paraneoplastic stiff person syndrome associated with colon cancer misdiagnosed as idiopathic Parkinson's disease worsened after capecitabine therapy

OBJECTIVES

To refresh clinical diagnostic dilemmas in patients presenting with symptoms resembling to those of parkinsonism, to report rare association of colon cancer and paraneoplastic stiff person syndrome (SPS), and to draw attention on the possible correlation of capecitabine therapy with worsening of paraneoplastic SPS.

METHODS

Case report of the patient with paraneoplastic SPS due to colon cancer that was misdiagnosed as idiopathic Parkinson's disease (iPD), whose symptoms worsened after beginning adjuvant capecitabine chemotherapy.

RESULTS

We describe a 55-year-old woman with subacute onset of symmetrical stiffness and rigidity of the truncal and proximal lower limb muscles that caused lower body bradykinesia, gait difficulties, and postural instability. Diagnose of iPD was made and levodopa treatment was initiated but failed to provide beneficial effect. Six months later, colon cancer was discovered and the patient underwent surgical procedure and chemotherapy with capecitabine thereafter. Aggravation of stiffness, rigidity, and low back pain was observed after the first chemotherapy cycle and capecitabine was discontinued. Furthermore, levodopa was slowly discontinued and low dose of diazepam was administered which resulted in partial resolution of the patient's symptoms.

CONCLUSION

Paraneoplastic SPS is rare disorder with clinical features resembling those of parkinsonian syndrome and making the correct diagnosis remains a challenge. The diagnosis of parkinsonian syndrome should be re-examined if subsequent examinations discover an associated malignant process. Although it remains unclear whether the patients with history of SPS are at the greater risk for symptoms deterioration after administration of capecitabine, clinicians should be aware of capecitabine side effects because recognition and appropriate management can prevent serious adverse outcomes.