Posts Tagged ‘Add new tag’

Spider Bite: Widow Spider Bite

There are more than 30,000 recognized spider species in the world. But only about 100 defend themselves aggressively and have fangs long enough to penetrate human skin and can cause harm to humans. Bites of the most spiders are painful but do not cause any harm. The venom that spiders use to hunt their prey can cause necrosis of skin and systemic toxicity. Bites of spiders like brown recluse spiders, widow spiders and very few other species can be life threatening. Specific treatment for spider bite like widow and brown recluse spiders is available, so offending spider should be tried to identify. In many cases it is seen that injury is by something else but spiders are attributed as the offender.

Widow Spider Bite:

The scientific name of widow spider is Latrodectus mactans. The bite of the female widow spider is dangerous and notorious due to its potent neurotoxin. The black widow spider is found in all of USA except Alaska. It is more common in Southeastern parts of USA. It is about 5 cm in length with a body of one cm. It is shiny black in color and has a red hourglass marking in the abdomen. The red widow and the brown widow are other dangerous types of widow spiders.

Bites are most common during summer and early autumn when their web is disturbed or when they are trapped or provoked. They spin their webs in logs, plants, rock piles, under stones or in dark areas like garages or outhouses. Buttocks are the site of bite if the person sits on a spider. It goes unnoticed at first or may be thought as a sharp pinprick. If examined properly two small red marks will be seen and there will be swelling around the marks. ? latrotoxin which is the most active component of the venom is yellowish and oily in color and may not cause any problem or it may be cause serious toxicity by binding irreversibly to nerves and cause release and depletion of acetylcholine, norepinephrine and other neurotransmitters. In less than half hour painful cramps spread from bite site to large muscles of trunk and limbs. Symptoms like salivation, vomiting, high blood pressure, diaphoresis, breathing difficulties, high pulse rate, weakness, headache, anxiety, urinary retention, hyperreflexia, fasciculation, uterine contraction and premature labor can occur. Peritonitis may develop, which is suggested by rigidity of abdominal muscles and excruciating pain. But there may not be any pain on pressure to abdomen. In very weak and frail person, elderly and young person it may cause renal failure, respiratory arrest, cardiac arrest, brain hemorrhage and death. Excruciating pain may last for several weeks or it may subside in a day.

Treatment of Widow Spider Bite:

At first cleaning of the bite site with plain water, ice packing, and tetanus prophylaxis should be given. If there is high blood pressure it requires specific antihypertensive therapy because it can not be controlled symptomatically. Specific equine antivenin is available but due to its high risk of anaphylaxis and serum sickness it should be reserved for serious cases only. The equine antivenin is administered intravenously relieve pain rapidly. One or two vials are usually sufficient.

Preventive measures like wearing full sleeve heavy shirts, full trousers (not half pant or bermuda’s), and hand gloves should be kept in mind while working outdoor and in dark areas indoor in the localities where widow spiders are commonly found.

Obsessive Compulsive Disorder (OCD)

Obsessive compulsive disorder (OCD) is characterized by obsessive thoughts and compulsive behaviors that hamper day to day activity. Most common forms of OCDs are fear of contamination by germs or dirt, so patients keep washing hands very frequently and having to check and recheck such actions as whether a door is locked or not. The degree by which individuals get affected varies, but all cases of OCD generally take up more than1 hour per day and are undertaken to relieve the anxiety triggered by the core fear. Doctors treating patients of OCD must ask specific questions regarding recurrent thoughts and behaviors, because patients often conceal their symptoms due to embarrassment by the content of their thought and their actions. Physicians must enquire about specific clues like, chafed and reddened hands or patchy hair loss which are due to repetitive hair pulling. Symptoms like depression, anxiety, eating disorders, and tics (eating of earth) are common. Some of the OCD are of benign nature, which does not cause any problem. But some are very much embarrassing and time consuming and harmful in the long run. Some patients are obsessive with counting numbers.

Read more...

All You Should Know about Parkinsonism & Parkinson’s Disease (PD)

Parkinson’s disease (PD) is the one of the commonest form of neurodegenerative disorders characterized by accumulation of presynaptic protein ?-synuclein and a variable degree of Parkinsonism. Parkinsonism is characterized by tremor at rest, rigidity, and bradykinesia (slowness of movements). Parkinsonism may also have symptoms like, shuffling gait and flexed posture. All forms of Parkinsonism are the result of reduction of dopaminergic transmission within the basal ganglion. 25% of all PD are genetically predisposed. Remaining 75% are idiopathic and sporadic. In United States alone more than one million patients of PD are present. Peak age at onset is 60 years (range from 35 to 85 years).

Parkinsonism is of two types; primary and secondary Parkinsonism. Primary Parkinsonism is due to familial, idiopathic, due to other neurodegenerative disorders like Alzheimer’s disease, Shy Drager syndrome etc. Genetically mediated primary Parkinsonism include Wilson’s Disease (hepatolenticular degeneration), Chediak Higashi disease, Fragile X syndrome, Huntington’s disease, Prion disease etc. Secondary Parkinsonism is due to repeated trauma (dementia pugilistica), infectious and post infectious diseases like neurosyphillis, postenchephalitic PD, hypoparathyroidism, non Wilsonian degeneration, drugs like, neuroleptics, antipsychotics, anti emetics, methyldopa, lithium, fluoxetine etc. Toxins like cyanide, manganese, methyl alcohol, carbon monoxide, carbon disulphide can cause secondary Parkinsonism.

Risk factors include a positive family history, male gender, head injury, exposure to pesticide, consumption of well water, and rural living. Incidence is high if there is combination of environmental factors and genetical predisposition. Factors which reduce incidence of PD include, drinking coffee, use of painkillers, estrogen replacement in postmenopausal women, and smoking.

Diagnosis of PD can be made confidently if at least two of the three cardinal signs are present, which are tremor at rest, rigidity, and bradykinesia. Tremor is present in 85% of patient with true PD, so diagnosis is difficult when tremor is absent and other two signs are present. Gradual onset of symptoms and if it is unilateral is also supportive in diagnosis. The most disturbing feature of PD is bradykinesia (slowness of movements) which interfere in day to day activities like walking, dressing, turning in bed, getting up from bed and rising from chair. Handwriting becomes bad or illegible. Speech becomes soft. Tremor starts in periphery first, like tremors of fingers of one hand and spread to the other next, than it spreads to the legs. Later on tremor appear on lips, tongue and jaw, but the head is spared.

Rigidity is uniform resistance to passive movements in a joint throughout the full range of motion, which gives characteristic ‘plastic’ quality. There may be also ‘cogwheel’ sensation, which is due to regular interruption of resistance during passive movement. Gait disturbance with shuffling short steps and a tendency to turn en block is an important sign of PD. Festinating gait is a classical sign of PD, which is due to combination of flexed posture and loss of postural reflexes, which causes the patient to ‘catch up’ with the body’s center of gravity. Other signs of PD include depression, anxiety, sleep disturbance, loss of smell (anosmia), sensory abnormality and pain, change in mood and behavior. Depression is present in almost half of the patients. Daytime drowsiness and frequent napping are common problems.

Studies of monozygotic and dizygotic twins have proved some of the PD as genetically predisposed. Four genes have been clearly linked to familial form of PD, and a number of genes can possibly cause PD. Among these PARK1 and PARK5 lead to an autosomal form of PD and PARK 2 and PARK 7 lead to autosomal recessive form of PD. Other genes which are thought to be a causative factor in development of PD include PARK 3, 4, 6, 9, 10 etc.

In PD dopaminergic cells die due to genetic weakness, environmental factors, protosomal dysfunction, and oxidative stress by free radicals. Pathological examination of brain reveals mild atrophy (shrinkage) with loss of melanin pigment of midbrain. Microscopically, there is degeneration of dopaminergic cells with the presence of Lewy Bodies (LB) in the remaining nerve cells or neurons. Lewy Bodies have high concentration of alpha-synucleinand is the hallmark of the diagnosis of PD.

Treatment of Parkinson’s disease: The goal of treatment of PD is maintenance of quality of life and avoids complications of drug therapy. In the early course of illness almost all symptoms of PD like rest tremor, rigidity, bradykinesia, and abnormal posture respond well to symptomatic treatment. Other symptoms like soft speech respond poorly. To prevent secondary disability regular physical activity programme is required, so regular physical activity is encouraged. Patient of PD should be mentally very strong to prevent worsening of the condition. Recent studies show that regular physical activity can promote neuroprotection against neurotoxins.

As soon as PD starts interfering with quality of life symptomatic drug therapy should be started. The ideal drug for treatment depends on the age of the patient, and cognitive status of the patient. Studies show that if therapy is initiated early, it reduces side effects in later part of the disease. Treatment can be started with levodopa or carbidopa. Initial dose is 25 to 100 mgs per day in three divided doses. Food increase bioavailability of the drug and it should be taken after food. The tablets should not be split, because it reduces controlled release property. The dose of levodopa/carbodopa should be adjusted according to the response. Other dopamine agonists can be combined with levodopa or carbidopa if monotherapy is not giving desired response. They include, non ergot alkaloids ropinirol, pramipexole, and ergot alkaloids pergolide, bromocriptine etc. Treatment of PD has to continue lifelong.

Treatment of Parkinsonism is also symptomatic like Parkinson’s disease. These two conditions are closely related to each other.

Truth About Alzheimer’s Disease

Alzheimer's disease (AD) is the most common cause of dementia in western countries. AD is caused to lack of acetylecholine in brain. Approximately 10% above 70 years have significant memory loss and at least more than half of this is due to Alzheimer's disease. AD most commonly presents as subtle loss of memory and it is followed by slowly progressive memory loss, and that has a course of several years (8-10 years). AD can occur at any time during adult life. Cost of treatment in USA is nearly $ 75,000 per year, which is a staggering sum of money, which also extracts a heavy emotional toll on family and friends and caregivers. Patho physiology of AD is diffuse atrophy of cerebral cortex and secondary enlargement of ventricular system. Neuritic plaques containing A? amyloids are seen in microscopy, and also accumulation of A? amyloids in the arterial walls of cerebral blood vessels. Four susceptible genes have been identified to cause AD.

Read more...