Israel Medical Association Journal

Background: The parasympathetic system and its main neurotransmitter, acetylcholine, contributes to homeostasis of inflammation. Cholinergic dysregulation is thought to contribute to the pathogenesis of inflammatory rheumatic diseases. Cholinesterase activity in patients with psoriatic arthritis (PsA) has not been investigated.

Objectives: To compare the cholinesterase activity in patients with PsA and immunocompetent controls and to explore the correlation between cholinergic status (CS) and PsA disease activity.

Methods: Serum acetylcholinesterase (AChE) and total cholinesterase activity were measured in patients with PsA (n=88) and matched controls (n=84). Cholinergic activity before and 3–6 months after the initiation of a biologic treatment was evaluated in seven patients with PsA.

Results: The levels of AChE and CS were similar in both PsA patients and controls. PsA patients treated with biologics had significantly lower levels of AChE and CS compared to patients treated with non-biologics: 447.4 vs. 526 substrate hydrolyzed/min/ml, P = 0.005, and 1360.9 vs. 1536, P = 0.029, respectively. We found an association between C-reactive protein levels, AChE activity (r = 0.291, P = 0.008), and cholinergic status (r = 0.247, P = 0.026) in patients with PsA but not in controls. No correlation between AChE activity, cholinergic status, and the indices of PsA disease activity was found. After initiating or switching biologic treatment in 7 patients, AChE levels remained stable.

Conclusions: We demonstrated similar cholinesterase activity in patients with psoriatic arthritis and controls, highlighting a potential effect of biologic treatment on cholinergic activity in patients with PsA.

Organophosphate and carbamate are mainly used to kill insects, thereby protecting livestock, crops, homes and communities. Yet, these compounds also convey great danger. OP[1] and CRB[2] poisoning is an important clinical problem, often life-threatening, especially in the pediatric population in rural areas where reaching a physician or hospital on time is difficult. We present a summary of accumulated toxicological knowledge as well as clinical and laboratory experience from a medical center serving a relatively vast rural area and pediatric population. We stress the importance of knowing how to recognize the classic signs of OP and CRB poisoning and when it is appropriate to investigate for such poisoning even in the absence of those signs. Like any medical emergency, OP and CRB poisoning requires prompt resuscitation and use of antidotes. Atropine, oxygen and fluids are the mainstay of therapy. Oximes, which were found useful in some cases of OP poisoning and useless in some cases of CRB poisoning, are absolutely safe as empiric treatment, which is often needed since the major differential diagnosis of OP poisoning is CRB poisoning that is clinically indistinguishable. We hope that continuing research will offer further insights into the management of such events, and we are confident that improved medical management of OP and CRB poisoning will result in a reduction of morbidity and other complications associated with intensive care procedures and hospitalization. 

Background: Splanchnic nerve stimulation evokes adrenomedullary catecholamine secretion via acetylcholine release and occupation of nicotinic cholinergic receptors on chromaffin cells.

Objectives: To assess whether among cultured adrenomedullary cells there exists a population that tonically secretes acetylcholine. If so, then blockade of enzymatic breakdown of acetylcholine by addition of a cholinesterase inhibitor to the medium would increase occupation of nicotinic receptors by endogenous acetylcholine and thereby induce catecholamine release.

Methods: Primary cultures of bovine adrenomedullary cells in 24-well plates (1 million cells per well) were incubated after 48–72 hours with fresh incubation medium (control), medium with added secretagogues (nicotine, angiotensin II, or K+) or the acetylcholinesterase inhibitor, edrophonium (10-7 to 10-³ M), for 1–20 minutes. Fractional release rates of epinephrine, norepinephrine and dopamine were compared to a control. We also examined whether co-incubation with edrophonium enhanced the effects of the secretagogues. All experiments were performed in quadruplicate and repeated three times.

Results: Nicotine, angiotensin II, and K+ each elicited time-related release of epinephrine, norepinephrine and dopamine by up to fourfold compared to the control. At all tested concentrations, edrophonium had no such effect. Co-incubation with edrophonium also failed to augment the secretory responses to nicotine, angiotensin II, or K+.

Conclusion: Bovine adrenomedullary cells in primary culture do not include a population of tonically active cholinergic cells.

Background: Organophosphates (OP) are frequently used as insecticides in the household and in agricultural areas, thus posing a risk for accidental exposure.

Objectives: To describe the characteristics, clinical course and outcome of 97 patients admitted to emergency rooms with a diagnosis of acute OP poisoning.

Methods: The clinical details of 97 patients were collected from 6 different hospitals in Israel. Diagnosis of intoxication was based on clinical findings, butyrylcholinesterase levels and, in several cases, the material brought to the hospital. Demographic, intoxication and clinical data were analyzed.

Results: The study group comprised 64 men and 33 women whose age range was 1–70 years old (mean 19.8 ± 17.1); more than one-third of the patients were less than 10 years old. Accidental exposure was the cause of intoxication in 51.5% of the patients, and suicide in 20.6% of exposures. Intoxication occurred at home in most patients (67%), and the route of intoxication was oral in 65% of them. The patients arrived at the hospital 20 minutes to 72 hours after intoxication. Nine patients were asymptomatic; 53 presented with mild intoxication, 22 with moderate, and 13 had severe intoxication, 5 of whom died. There was a direct correlation between the degree of inhibition of butyrylcholinesterase levels and the severity of intoxication. Treatment included decontamination and antidotal medication. Duration of hospitalization ranged between 1 and to 14 days (average 2.9 days).

Conclusions: Organophosphates may cause severe morbidity and mortality. Medical staff should therefore be aware of the clinical manifestations and the antidotal treatment for this poisoning.