Healthpedia

Dengue Fever Detached Retina Diphtheria Dyslexia

Depression Diabetes Mellitus Dysentery

 

Dengue Fever

 

Definition:

Dengue fever is an infectious disease carried by mosquitoes and caused by any of four related Dengue viruses: DEN-1, DEN-2, DEN-3, and DEN-4. A person can be infected by at least two, if not all four types at different times during a life span, but only once from the same type. People get Dengue virus infections from the bite of an infected Aedes mosquito that usually feeds in the daytime and is frequently found in cities. It is rarely found in mountainous areas above 4,000 feet. Dengue is not contagious from person to person.

 

Who is at risk?

Resident and the travelers to the endemic areas such as the tropical countries of the Indian subcontinent, Southeast Asia, Southern China, Central and South America, the Caribbean (including Puerto Rico and the US Virgin Islands), Mexico, and Africa.

Anyone who is bitten by an infected mosquito can get Dengue fever. Risk factors for Dengue hemorrhagic fever include a person's age and immune status, as well as the type of infecting virus.

People who were previously infected with one or more types of Dengue viruses are thought to be at greater risk for developing Dengue hemorrhagic fever if infected again.

 

Symptoms:

1. The illness begins with the sudden onset of flu-like symptoms including fever, headache, muscle aches and joint pain, pain behind the eyes and a faint rash. The fever usually lasts from three to five days, and rarely more than seven days.
2. While the disease is often mild and self-limiting, a more severe lethal form called Dengue haemorrhagic fever can occur: Loss of appetite, vomiting, intense abdominal pain, shock and bleeding from the nose or under the skin.
3. The occurrence of DHF may be associated with those who are immune-suppressed, experiencing their second infection, or being under the age of fifteen.
4. With respect to the four distinct but closely related DF virus serotypes, recovery from an initial infection caused by one strain provides lifelong immunity against that stereotype only. There is good evidence that suggests that any subsequent re-infection by another strain of the DF virus increases your risk of acquiring the more serious disease, Dengue haemorrhagic fever.

 

Treatment:

There is no specific treatment available. Intravenous fluids and oxygen therapy are often used for patients who experience shock during their illness.

 

Prevention:

There is no vaccine for preventing Dengue.

Primary prevention

• For residents living in areas infested with Aedes aegypti, the measure is to eliminate the places where the mosquito lays her eggs (e.g. artificial containers that hold water). Items that collect rainwater or are used to store water (e.g. plastic containers) should be covered or properly discarded. Pet and animal watering containers and vases with fresh flowers should be emptied and scoured at least once a week. This will eliminate the mosquito eggs and larvae and reduce the number of mosquitoes present in these areas.
• For travelers to areas with Dengue as well as residents living in areas, the risk of being bitten by mosquitoes indoors is reduced by utilization of air conditioning or windows and doors that are screened.
• Wear long sleeve shirts and pants that are light in colour and apply proper application of mosquito repellent. These repellants should contain 20% to 30% DEET as the active ingredient on exposed skin and clothing decreases the risk of being bitten by mosquitoes.
• Avoid using scented products such as perfume and hairspray.

Secondary prevention

Early medical intervention for Dengue hemorrhagic fever may prevent serious complications.

Back to top

 

Depression

 

Definition:

No one knows the exact cause of depression, but it may be related to an excess or lack of certain brain chemicals known as neurotransmitters (serotonin and noradrenaline). Many people do not receive treatment because they may not recognize the disorder, or they are discouraged to seek treatment due to shame or stigma. There are three types of depressive illness:

1. Major Depressive Disorder.
2. Dysthymia.
3. Bipolar Disorder.

 

Who is at risk?

1. Family history of the disorder: Children and adolescents with depression are also likely to have a family history of depression;
2. Female: In childhood: Boys and girls at equal risk for depressive disorders. From adolescence onwards, girls are twice as likely as boys to develop depression;
3. People under stress in the form of loss, especially death of close family members, close friends or loved ones;
4. People who had a break up of a romantic relationship or a divorce;
5. People with chronic illnesses such as Parkinson's diseases, cancer and diabetes;
6. People who have experienced traumas including natural disasters;
7. People who have behavioural or learning disorders;
8. People who have low self-esteem;
9. People who have a care-giving role for patients with chronic illness.

 

Symptoms:

Major Depressive Disorder: >5 symptoms during the same 2-week period.

• Constant depressed mood with negative thoughts.
• Lack or loss of interest in hobbies or other pleasurable activities.
• Changes in weight and appetite.
• Insomnia (difficulty with sleeping) or excessive sleeping.
• Excessive tiredness and fatigue.
• Unusual guilt and excessive feelings of worthlessness, hopelessness, or helplessness.
• Difficulty with thinking clearly, making decisions or concentrating.
• Anxiety or slowing of physical movements.
• Chronic thoughts of death or suicide.

Dysthymia - Less severe form of depression

• Depressed mood lasting at least 2 years (1 year in children).
• 2 of the symptoms listed in Major Depressive Disorder.

Bipolar Disorder - Alternating depression with mania

• Depression phase - Major Depressive Disorder symptoms.
• Mania phase - Abnormally elevated mood, irritability, agitation, inflated self-esteem, easily distracted, decreased need for sleep, excessive talkativeness, and racing thoughts. Examples of grandeur behaviour are "giving away money" and "making cakes for everybody in the company".

 

Treatment:

Doctors usually treat depression in two stages. Acute treatment with medications helps relieve symptoms until you feel well. Once your symptoms ease, maintenance treatment typically continues for six to 12 months to prevent a relapse. It's important to keep taking your medication even though you feel fine and are back to your usual activities.

 

Medications include:

• Selective serotonin reuptake inhibitors (SSRIs): e.g. fluoxetine (Prozac), paroxetine (Paxil), sertraline (Zoloft) and escitalopram (Lexapro).
• Tricyclic antidepressant: e.g. amitriptyline.
• Tetracyclic antidepressants: e.g. mirtazapine (Remeron).
• Monoamine oxidase inhibitors (MAOIs): e.g. phenelzine (Nardil) and tranylcypromine (Parnate).
• Stimulants. e.g. methylphenidate (Ritalin) and dextroamphetamine (Dexedrine) in addition to an antidepressant because most antidepressants are slow to work.
• Lithium and mood-stabilizing medications. Doctors prescribe lithium, valproic acid and carbamazepine (Tegretol) to treat bipolar depression.

 

Cognitive Behavioural Therapy (a method of psychotherapy)

Cognitive Behavioural Therapy (CBT) can be very empowering. It helps us to take control over our thoughts, rather than allowing our thoughts to control us. CBT provides valuable skills and techniques to observe our thought patterns and begin the process of retraining them, enabling us to correct any negative thought habits or misinterpretations we may have that worsen the effects of depression. Currently the most effective treatment for major depression is considered to be a combination of antidepressant medication and CBT.

 

Electroconvulsive therapy (Electric shock to the head)

Experts are not sure how this therapy relieves symptoms of depression. The seizure may affect levels of neurotransmitters in the brain. Often confusion would arise and last for a few minutes to several hours. Some people suffer memory loss for several weeks. This therapy is usually used for people who don't respond to medications and for those at high risk of suicide.

 

Prevention of disease relapse:

• DO NOT stop taking your medicine or change the dose by yourself.
• DO NOT take any other medication, medications of friends or relatives, or herbal supplements without talking to your doctor. These medicines may interfere with the effectiveness of the anti-depressants. They may worsen your symptoms, or cause severe and even fatal side effects.
• Remember that medication may take up to several weeks or months to work.
• Continue with counseling or behavior therapy programs as directed.
• Avoid foods with excessive caffeine and alcoholic beverages.
• Keep a diary of your moods and share it with your doctor & seek immediate medical attention if you have thoughts of harming yourself such as suicidal thoughts!

Back to top

 

Detached Retina

 

Definition:

Retina is a layer of light-sensitive tissue that lines the inside of the eye and converts light into electrical signals. When the retina detaches, the layer is lifted or pulled from its normal position. If not promptly treated, retinal detachment can cause permanent vision loss.

 

Who is at risk?

1. People extremely nearsighted;
2. Family history of retinal detachment;
3. Past history of retinal detachment;
4. After injury to the eye;
5. Have other eye diseases or disorders.

People are more prone to retinal detachments if they have a hole or a tear in their retina. The hole or tear allows fluid to seep underneath, weakening the attachment so that the retina becomes separated from other layers. The condition is more common in man, especially after middle age.

 

Symptoms:

Retinal detachment is not painful. Common symptoms include:

• Sudden or unusual increase in "floaters", which are showers of dark spots obscuring field of vision
• Bright flashing lights in the eye
• Appearance of a curtain over the field of vision

 

Treatment:

Small holes and tears in the retina can be treated with laser surgery or a treatment called cryopexy, which uses cold temperature to "weld" the retina back into place. The procedures can be performed in an outpatient basis. Those severely affected may need more complicated surgery in a hospital. Retinal detachment is a medical emergency. Anyone experiencing the symptoms of retinal detachment should see an ophthalmologist immediately.

 

Prevention:

Patients at high risk of retinal detachment should have their eyes examined periodically. Preventive laser or freezing treatment may be offered to areas of weakness in the retina to prevent it from detaching.

Back to top

 

Diabetes Mellitus

 

Definition:

Diabetes mellitus is a chronic disorder characterized by a raised blood glucose level resulting from insulin deficiency, insulin resistance or both. In Type I or insulin-dependent diabetes (IDDM), little or no insulin is produced. In Type II or non-insulin-dependent diabetes (NIDDM), there is reduced insulin secretion and the body cells do not react to insulin. It is estimated that ~10% of Hong Kong population suffer from it. It is the eighth most common cause of death in Hong Kong, accounting for about 1.7% of all deaths. Diabetes increases the risk of stroke, ischemic heart disease, high triglyceride, foot gangrene, retinopathy, nephropathy and neuropathy. The optimal control of the blood glucose level and cardiovascular risk factors in patients with diabetes has been proven to reduce complication rates and is cost effective.

 

Who is at risk?

• Aged - The risk increases with age (45);
• People with family history of diabetes (first degree);
• A history of gestational diabetes;
• People with blood pressure with reading> 140/90 mm/Hg;
• People having inactive lifestyle;
• Easterner more than white;
• People with metabolic syndrome (obese with BMI>23, hypertensive and high level of insulin at blood and microalbumin in urine).

 

Symptoms:

1. Increased urination: It may be caused by high blood sugar.
2. Excessive thirst or hunger: Some people with untreated diabetes often feel like eating all the time and their appetite may be greater than normal for them.
3. Weight loss: Losing weight quickly without trying to could be a symptom of diabetes.
4. Fatigue: High blood glucose levels can make you feel tired. If you are more tired than usual, and changes in your lifestyle are not the cause, it may be a sign of diabetes.
5. Wounds that don't heal. Untreated diabetes can cause poor wound healing. Watch for infections or cuts that don't heal in a reasonable amount of time after using first aid.
6. Blurred vision.

 

Treatment:

• To survive, people with type 1 diabetes must have insulin delivered by injections or a pump.
• Many people with type 2 diabetes can control their blood glucose by following a careful diet and exercise program, losing excess weight, and taking oral medication.
• Many people with diabetes also need to take medication to control their cholesterol and blood pressure.

Parameter	Optimal control
Fasting glucose (mmol/L)	4.0-6.0
Postprandial glucose (mmol/L)	<8
HbA1c (%)	<7 %
Body Mass Index (<BMI)	<23
Systolic Blood pressure (mmHg)	<130 mmHg
Diastolic Blood Pressure (mmHg)	<80 mmHg
LDL cholesterol (mmol/L)	<2.6 mmol/L
Triglyceride (mmol/L)	<1.7 mmol/L
HDL cholesterol (mmol/L)	>1.1

 

Prevention:

Prevention or delay of diabetes

There are no known methods to prevent type 1 diabetes.

Lifestyle interventions included diet and moderate-intensity physical activity (such as walking for 2 1/2 hours each week).

Studies have also shown that medications have been successful in preventing diabetes in some population groups. Examples are metformin and acarbose.

Prevention of diabetes complications

Diabetes can affect many parts of the body and can lead to serious complications such as blindness, kidney damage, and lower-limb amputations. Working together, people with diabetes and their health care providers can reduce the occurrence of diabetes complications by controlling the levels of blood glucose, blood pressure, and blood lipids and by receiving other preventive care practices in a timely manner.

1. Glucose control: Benefits people with either type 1 or type 2 diabetes. In general, for every 1% reduction in results of A1C blood tests (e.g., from 8.0% to 7.0%), the risk of developing microvascular diabetic complications (eye, kidney, and nerve disease) is reduced by 40%.
2. Blood pressure control: Reduce cardiovascular disease (heart disease and stroke) by approximately 33% to 50% and can reduce microvascular disease (eye, kidney, and nerve disease) by approximately 33%. In general, for every 10 millimeters of mercury (mm Hg) reduction in systolic blood pressure, the risk for any complication related to diabetes is reduced by 12%.
3. Control of blood lipids: Improved control of cholesterol or blood lipids (for example, HDL, LDL, and triglycerides) can reduce cardiovascular complications by 20% to 50%.
4. Preventive care practices for eyes, kidneys, and feet:
   • Detecting and treating diabetic eye disease with laser therapy can reduce the development of severe vision loss by an estimated 50% to 60%.
   • Comprehensive foot care programs can reduce amputation rates by 45% to 85%.
   • Detecting and treating early diabetic kidney disease by lowering blood pressure can reduce the decline in kidney function by 30% to 70%.
   • Treatment with ACE inhibitors and angiotensin receptor blockers (ARBs) are more effective in reducing the decline in kidney function than other blood pressure lowering drugs.

Back to top

 

Diphtheria

 

Definition:

Diphtheria is a life-threatening infection that usually attacks the throat and nose. Diphtheria is spread by respiratory secretions and physical contact. It is caused by a bacterium called Corynebacterium diphtheriae. It can produce a toxin which is carried in the bloodstream and can damage the heart and the nerves.

 

Who is at risk?

• Diphtheria is most common in developing countries where people live in crowded conditions with poor sanitation.
• People who are not immunized, especially children are at greatest risk.
• It has become extremely rare in the developed world, including Hong Kong.

 

Symptoms:

• The onset of disease is usually gradual. Early symptoms include fatigue, fever, mild sore throat and problems with swallowing.
• Symptoms such as nausea, vomiting, chills and high fever can occur.
• The infection often results in a whitish grey covering in the throat, which can get dislodged into the windpipe and cause breathing difficulties.

 

Treatment:

• Diphtheria is a medical emergency. The patient should be hospitalized and isolated until fully recovered. Delay in treatment can result in death or long-term heart disease.
• Antibiotics are necessary. Antitoxins should be given to neutralize the toxins produced by the bacteria.
• Some patients might even need mechanical help in their breathing.

 

Prevention:

• There is an effective vaccine for diphtheria. Most developed countries have included the vaccine in their infant immunization programs. It is usually given in a combination shot with tetanus and pertussis vaccines, known as DTP or triple vaccine.
• The diphtheria vaccine is also included in the new 4 in 1, 5 in 1 or 6 in 1 infant vaccines.
• A child should have received four DTP shots by 18 months of age, with a booster shot at age 4 years to 6 years. After that, diphtheria and tetanus boosters should be given every 10 years to provide continued protection.

Back to top

 

Dysentery

 

Definition:

Dysentery refers to any infectious conditions of the gut that result in bloody diarrhea. The most common culprits are Shigella and Salmonella, which are common bacterial pathogens of the gastrointestinal tract. Dysentery can also be caused by an amoeba parasite.

 

Who is at risk?

• Dysentery is transmitted directly by fecal material of a patient/carrier or indirectly through contaminated food and water.
• The disease is most common in tropical countries, but can occur in all parts of the world.
• It is more common in young children, though people of all ages are vulnerable.
• Outbreaks of dysentery are common in people living in over-crowded institutions.

 

Symptoms:

• Incubation period is usually 1 - 3 days, but can be up to 7 days.
• The illness is characterized by sudden onset of fever, diarrhea, cramping abdominal pain with nausea or vomiting.
• Patients may pass very frequent stools in small amounts and may strain painfully, without success, to evacuate the bowels.
• The stool often contains blood and mucus. Some may experience have high fever.

 

Treatment:

• Patients with bloody diarrhea should consult a physician as there can be other possibilities.
• Dehydration must first be treated intravenously or orally with electrolyte solutions.
• Healthy adults with mild symptoms may recover on symptomatic treatment.
• Small children, elderly, or those with underlying medical conditions may need antibiotics.
• Dysentery caused by ameba needs to be treated with different kinds of drugs.

 

Prevention:

• Infection may occur after consuming a small number of the germs. Therefore, chance of spread among household members or in institutions can be very high unless strict personal hygiene is observed.
• Purchase fresh food from reliable sources. Do not patronize illegal hawkers.
• Avoid high-risk food like shellfish, raw food or semi-cooked food.
• Travelers to places where dysentery is common need to be cautious with what they eat and drink apart from observing strict personal hygiene.

Back to top

 

Dyslexia

 

Definition:

Dyslexia is a specific type of learning difficulty caused by the brain's inability to translate written images received from the eyes into meaningful language.

It is helpful to think of dyslexia as an information processing difficulty. People with dyslexia would have problems with reading, writing, spelling and sometimes mathematics and musical notation. Dyslexics may have a different state of mind for intellectual functioning. In areas where such processing is not needed, the person may not encounter difficulties at all. Very often dyslexics have specific strengths in:

• Creativity and innovative thinking
• Intuitive problem solving and troubleshooting
• Physical activities

 

Who is at risk?

• Family history of dyslexia
• Boys (The condition is 3 to 4 times common in the male)
• History of language delay
• History of not attending to the sounds of words, confusing words that sound alike, or having trouble with rhyming games

 

Symptoms:

Most dyslexic children present reading and writing difficulties in school. They are performing at a level well below what is expected from the age and general intelligence of the child. Other signs include:

• Putting letters and figures the wrong way round
• Difficulty with sequences/patterns
• Poor organization skill or time management
• Short-term memory or concentration problems

 

Treatment:

There is no cure for dyslexia, but early recognition might help. Before starting any treatment, an evaluation must be done. This is to determine the child's specific area of disability and relative strengths. The school and parents should develop a plan to meet the child's needs. An appropriate treatment plan will enable the child to spend more time strengthening the weaknesses while utilizing the strengths.

 

Prevention:

There is no way to prevent dyslexia, but early discovery and intervention can provide remedy and prevent secondary emotional problems.

Back to top