Medicine Newbie

Monday, 25 April 2016

Liver structure & function, tests and diseases

ANATOMY OF THE LIVER

Anatomy - Liver explained clearly
https://youtu.be/BTGkB8nOu7g

Anatomy - Liver structure, hepatic blood flow and bile
https://youtu.be/P5_BxsbmXcA

Anatomy - Liver anatomy and blood supply
https://youtu.be/a1vgszd5_yM

Anatomy - Histology of the liver
https://youtu.be/KtFJvlEDE2I

Anatomy - Shotgun Histology liver
https://youtu.be/eLpynp35i7U

Anatomy - Liver histology 1/7
https://youtu.be/S9hsMSnyeLI

LIVER PHYSIOLOGY

Physiology - Hepatic physiology 1 > Functions of the liver
https://youtu.be/EfZB83u_-O8

Physiology - Hepatic physiology 2 > Portal circulation
https://youtu.be/czTB8RpY0ag

Physiology - Hepatic physiology 3 > Sinusoids & surrounding cells
https://youtu.be/71wQle8UguU

BILIRUBIN METABOLISM

Biochemistry - Bilirubin metabolism
https://youtu.be/dJ_dasmimE4

Biochemistry - Bilirubin pathway
https://youtu.be/4K9i7MPeuVg

Biochemistry - Bilirubin metabolism and diseases
https://youtu.be/-bZmC07L394

Biochemistry - Bilirubin metabolism > Jaundice
https://youtu.be/uOK_TGNQ7mM

LIVER FUNCTION TESTS (LFT)

Biochemistry - Liver function tests (LFTs) explained clearly
https://youtu.be/bFdTgty0T0I

Biochemistry - Liver function tests (LFT)
https://youtu.be/A36Wt5hDkoE

Biochemistry - Liver tests - Use and interpretation
https://youtu.be/LErNbfx0qPA

Biochemistry - Interpretation of LFTs (Liver function tests)
https://youtu.be/UrrXITkyb2c

Biochemistry - Important liver values > Albumin, ALT, ALP & AST
https://youtu.be/NAB-jnD3JWo

LIVER DISEASES

Pathology - Liver disease explained clearly > Introduction to acute & chronic liver diseases
https://youtu.be/7onWXWOV3io

Pathology - Pathophysiology of cirrhosis > Alcoholic liver disease
https://youtu.be/03ijM2bg08w

Tuesday, 12 April 2016

Dengue

English: Dengue
Malay: Denggi

What is dengue?
http://www.who.int/features/qa/54/en/

Dengue is a viral disease spread by mosquito bite. The Aedes egyptii mosquito is the carrier of the dengue virus.

1. When does dengue occur?

It can occur anytime. It occurs mainly during the hot and dry season and with occasional rain. Breeding grounds can be outside or inside the house.

Outside the house ...

Watering the plants can help to form puddles on the uneven floor around the flowerpots. If the puddles don't dry up fast, mosquitoes can breed as they just need overnight stagnant water.

Rainwater is trapped in various containers improperly disposed off by unthinking users. Rainwater also collects in unused building materials, paint can lids, disused plastic, leaves that curl and can hold water, slippers, drains, clogged gutters etc.

Inside the house ...

Stagnant water provides a good breeding ground for mosquitoes. It doesn't matter whether the home is in the urban or rural area. Urban homes tend to have more decor and flower vases containing water. Urban homes have a lot of clutter and sunshine hardly hits the interior spaces. The interior spaces are often cold and damp .... a perfect hybernating space for mosquitoes while waiting for water to breed. Thus, it is not surprising that dengue sufferers are often found within urban homes rather than rural homes, which have plenty of sunshine and are often drier internal environment.

Most homes today are equipped with basic appliances - the usual kitchen utensils and bath utilities. These don't need daily attention and are often left as they are till the next spring cleaning activity. Flower vases with water, dishes and bowls left to dry but not properly drained, draining boards that are not frequently drained, stagnant water at the base of refrigerators, water in the containers that hold legs of cupboards, etc are among the many possibilities for dengue development.

Inside the toilet, open water tanks which are untreated with Abate, water in pails which are left overnight or for longer period, dippers half-filled with water, wet toilet slippers, water closets (WC) which are left unused for long periods, toilet floors with stagnant water at the corners and near the drainage holes, empty shampoo bottles left lying around on the toilet floor, dirty diapers left on the toilet floor, empty soap wrappers left on the toilet floor, and various other things found in the toilet, are good breeding grounds for the dengue mosquito.

2. Dengue FAQ
http://www.cdc.gov/dengue/faqfacts/index.html

3. What are the signs and symptoms of dengue?

Weakness that gradually worsens and the infected patient becomes fatigued overnight. The weakness is accompanied by an unusual fever and the entire body becomes painful. There is loss of appetite (LOA), altered taste sensation (food does not taste like food anymore), and weight loss. Sometimes the white of the eye appears red, due to hemorrhage of the capillaries in the eyes.

The patient is usually rushed to the hospital A&E, where dengue is diagnosed and the patient is warded for immediate treatment.

Since the patient is already very weak and cannot get up to go to toilet, a bed-pan is a must. Some patients prefer to wear pampers. A relative or family member may want to accompany the patient since the patient has no energy to do much except sleep and breathe. The patient is moved around in wheelchair.

4. How is dengue monitored?

This is an acute infection. It is short-lived. It peaks between 3-5 days and subsides within 2 weeks.

Platelet count is monitored at the hospital. The platelet count drops very low and can be as low as 20.

Patients are discharged home once the platelet count is sufficiently high. Normal platelet count is more than 300 in adults.

5. What food can the dengue patient eat?

Since the patient has altered taste sensation, he/she has no appetite and will not eat. But the patient must be forced to eat.

Among traditional food that can be fed to help overcome dengue are crab soup and bitter papaya leaf juice.

Crab is ketam nipah - a large crab variety that survives in the freshwater marshes by rivers. They sell these crabs in Sabak, Kelantan @ 3 crabs for RM10. They are cleaned and cooked as soup with added ginger, lemon grass (serai), and salt. Drinking the crab soup is sufficient if the patient cannot eat the crab meat.

The papaya leaf juice is prepared by pounding young papaya shoots and squeezing the juice through a sieve. Only a tablespoon a day is sufficient. It is very bitter. Some people add honey, but it is still bitter and difficult to take.

6. How is the patient monitored after being discharged?

The patient is scheduled for regular visits to the clinic (eg Klinik Staf USM) at weekly intervals, to monitor recovery progress - platelet count (if any) and overall general health.

Patients are still very tired (fatigued) after 2 weeks from the first instance of dengue diagnosis. They must be accompanied by a relative or family member when attending post-dengue clinic.

7. How is the patient's living area cared for?

Dengue is a notifiable disease. Once the health clinic is notified, health officers visit the residential area and look for possible dengue breeding grounds. Fogging notices are posted on gates or postal boxes of each home, usually early in the morning of the day of fogging, at about 9 am. Sometimes the home owners have all gone to work by that time, so they won't know till they get home in the evening.

External fogging kills the mosquitoes and larvae. Fogging is done between 6 pm and 7 pm, a time when the mosquitoes come out to feed.

Internal fogging (inside the homes) is done after external fogging between 6 pm and 7 pm.

8. Is fogging safe?

The home is safe after 30 minutes has passed after fogging. The strong oil odour is still in the house long after this and may last up to 1-2 days. Aerosol marks can be found on glass surfaces, glass windows, TV monitors, laptops etc.

9. Is repeated fogging necessary?

Fogging is repeated every 2-3 days, as long as there are dengue patients identified and warded from a particular residential area.

If 5 patients are identified in a particular residential area (taman perumahan), then it can be expected to have continuous fogging for extended periods.

If there is no dengue patient reported from a particular housing area, it means that the area is dengue-free and no fogging is necessary. This often confuses the residents as when there are plenty of mosquitoes, residents tend to think all mosquitoes are dengue mosquitoes, which is untrue.

The usual mosquitoes that build up among flower pots and in the bushes around and nearby houses are often not dengue mosquitoes, but they are a nuisance. They disrupt the peace and happy living environment and mood. They bite and residents have a hard time getting rid of them.

The usual insect spray seems not to help. Burning treated mosquito coil also seem not to work. So at this present time, there is no cure from the menacing non-dengue mosquitoes.

10. Does fogging disrupt lives?

Yes, because the fogging team starts fogging at 6 pm. Most people work outside the home and only return home by 6 pm. They are often exhausted from their daily 8 am-5 pm weekday work. They just want to eat dinner and rest for the day. Fogging activities tend to disrupt their daily routine.

External fogging by the health authorities, 10 January 2016

Thursday, 24 March 2016

Lymph Nodes, Lymphadenitis and Lymphadenopathy

Do we all have lymph nodes?

Yes. # of lymph nodes in the body: ~ 600

What are lymph nodes? How big are our lymph nodes?
Structure and function of lymph nodes:

Lymph nodes are small, ovoid nodules normally ranging in size from a few millimeters to 2 cm.
They are distributed in clusters along the course of lymphatic vessels located throughout the body.
The primary function of lymph nodes is to filter out microorganisms and abnormal cells that have collected in lymph fluid.
Node dimensions: In general, lymph nodes greater than 1 cm in diameter are considered to be abnormal. eg 1.7 cm x 1.8 cm x 2.2 cm ... before commencing antiobiotics (Amoxycillin + clavulanate)

Definitions:

Lymphadenopathy refers to nodes that are abnormal in either size, consistency or number.
Lymphadenitis is the inflammation or enlargement of a lymph node.

Physical examination (PE):

Careful palpation of the submandibular (bawah dagu), anterior and posterior cervical (leher), supraclavicular (pangkal leher), axillary (ketiak) and inguinal (celah kangkang) nodes can be accomplished in a short time and will identify patients with generalized lymphadenopathy.

A localised cervical lymphadenopathy is either on the right side or left side of the neck. It can be solitary or aggregated (like a bunch of grapes).

Characteristics:

Location - Depends on underlying etiology
Number - Single, local groupings (regional), or generalized (ie, multiple regions)
Size/shape - Normal lymph nodes range in size from a few millimeters to 2 cm in diameter; enlarged nodes are greater than 2-3 cm with regular/irregular shapes
Consistency - Soft, firm, rubbery, hard, fluctuant, warm
Tenderness - Suggestive of an infectious process but does not rule out malignant causes

Classification by anatomical location (the region drained by the nodes) and incidence:

1. “Generalized lymphadenopathy” if lymph nodes are enlarged in two or more non contiguous areas (25%). eg Cytomegalovirus.

2. “Localized lymphadenopathy” if only one area is involved (75%):

Head and neck (55%)
Supraclavicular (1%)
Axillary (5%)
Inguinal (14%)

Further breakdown of location of lymph nodes:

(i) Head and neck (55%)
Submandibular

tongue
submaxillary gland - dental caries/abscess
lips and mouth
conjunctivae

Submental

lower lip
floor of mouth
tip of tongue
skin of cheek

Jugular

tongue
tonsil
pinna
parotid

Posterior cervical

scalp and neck
skin of arms and pectorals
thorax
cervical and axillary nodes

Anterior cervical, mediastinal - Epstein-Barr virus (EBV) (mononucleosis)

Suboccipital

scalp and head

Postauricular

external auditory meatus
pinna
scalp

Preauricular

eyelids and conjunctivae
temporal region
pinna

(ii) Supraclavicular (1%)

Right supraclavicular node

mediastinum; mediastinal - Epstein-Barr virus (EBV) (mononucleosis)
lungs
esophagus

Left supraclavicular node

thorax
abdomen
via thoracic duct

(iii) Axillary (5%)

Axillary

arm
thoracic wall
breast

Epithrochlear

ulnar aspect of forearm and hand

INVESTIGATIONS

Skin test/Mantoux test - walk-in test done at Medical clinic (KPP). Uses 1 ml of tuberculin or purified protein derivative (PPD). To confirm the diagnosis of tuberculous lymphadenopathy; alternative is interferon-gamma release assays (IGRA). TRO TB; check for recent/past exposure to TB organism. Results are read on the 4th day: eg a 15 mm induration is considered "positive" or evidence of having antibodies/immunity to the TB organism or previous exposure - could be a recent house renovations with a coughing worker; could be a coughing husband, etc.
Blood test: ESR, FBP. TRO bacterial/viral infection. Turnaround time (TAT) for blood results is 1 week from Hematology. CBC count - Elevated WBC count may indicate an infectious etiology. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) - Elevated ESR and CRP are nonspecific indicators of inflammation.
Serology. Monospot or Epstein-Barr Virus (EBV) serologies. To confirm the diagnosis of infectious mononucleosis.
CT Scan - location, size and # of abnormal lymph nodes involved; contents of lymph node - fluid/pus or cellular. Interpretations and Radiology reports are available by the 3rd day.
CXR (chest x-ray) - Chest radiography may be helpful in determining pulmonary involvement or spread of lymphadenopathy to the chest. TRO pulmonary TB (PTB). Films are available online the same day. Radiology report is made available online.
Ultrasound. Ultrasonography may be useful for verifying lymph node involvement and taking accurate measurements of enlarged nodes. Ultrasound is not able to differentiate between benign and malignant forms of lymphadenopathy.
Node biopsy: FNAC versus excisional biopsy ... performed under local anaesthesia ... procedure does not need fasting; performed after 1 week course of antibiotics (Amoxycillin + calvulanate). Drainage if filled with pus or fluid. Aspirates, if any.
Gram stain of aspirated tissue. To evaluate bacterial etiologies.
Culture and Sensitivity (C&S). Culture of aspirated tissue or biopsy specimen. To determine the causative organism and its sensitivity to antibiotics.
Liver function tests (LFT). May indicate hepatic or systemic involvement; elevated transaminase levels can be seen in infectious mononucleosis.

CAUSES

In most cases, a careful history and physical examination will identify a readily diagnosable cause of the lymphadenopathy. Refer to the algorithm for investigating lymphadenopathy. The causes are categorized into 3 types:

Diagnostic causes:

upper respiratory tract infection (URTI),
pharyngitis (sakit tekak),
periodontal disease (penyakit gigi dan gusi),
conjunctivitis (sakit mata),
lymphadenitis (radang noda limfa),
tinea (kulat),
insect bites (gigitan serangga),
recent immunization (imunisasi terhampir),
cat-scratch disease (cakar kucing)
dermatitis (radang kulit)

Suggestive causes:

mononucleosis
syphilis
lymphoma
HIV

Unexplained causes:

if generalised - review epidemiologic clues. Patients with generalized lymphadenopathy will need further diagnostic evaluation that often includes biopsy.
if localized - review history, regional examination and epidemiologic clues. Patients with localized lymphadenopathy + a worrisome clinical picture will need further diagnostic evaluation that often includes biopsy.

LYMPHADENITIS

Infectious agents/causes and lymphadenitis and characteristics:

Bartonella henselae (catscratch disease) – Single-node involvement determined by scratch site; discrete, mobile, nontender
Coccidioides immitis (coccidioidomycosis) – Mediastinal
Cytomegalovirus – Generalized
Epstein-Barr Virus (EBV) (mononucleosis) - Anterior cervical, mediastinal, bilateral; discrete, firm, nontender
Francisella tularensis (tularemia) - Cervical, mediastinal, or generalized; tender
Histoplasma capsulatum (histoplasmosis) – Mediastinal
Atypical Mycobacterium - Cervical, submandibular, submental (usually unilateral); most commonly in immunocompetent children aged 1-5 years
Mycobacterium tuberculosis - Mediastinal, mesenteric, anterior cervical, localized disease (discrete, firm, mobile, tender); generalized hematogenous spread (soft, fluctuant, matted, and adhere to overlying, erythematous skin)
Parvovirus - Posterior auricular, posterior cervical, occipital
Rubella - Posterior auricular, posterior cervical, occipital
Salmonella – Generalized
Seborrheic dermatitis, scalp infections - Occipital, postauricular
Staphylococcus aureus adenitis - Cervical, submandibular; unilateral, firm, tender
Group A streptococcal (GAS) pharyngitis - Submandibular and anterior cervical; unilateral, firm, tender
Toxoplasma gondii - Generalized, often nontender
Viral pharyngitis - Bilateral postcervical; firm, tender
Yersinia enterocolitica - Cervical or abdominal
Yersinia pestis (plague) - Axillary, inguinal, femoral, cervical; extremely tender with overlying erythema

Immunologic or connective tissue disorders causing lymphadenitis are as follows:

Juvenile rheumatoid arthritis
Graft versus host disease

Primary diseases of lymphoid or reticuloendothelial tissue causing lymphadenitis are as follows:

Acute lymphoblastic leukemia
Lymphosarcoma
Reticulum cell sarcoma
Non-Hodgkin lymphoma
Malignant histocytosis or histocytic lymphoma
Nonendemic Burkitt tumor
Nasopharyngeal rhabdomyosarcoma
Neuroblastoma
Thyroid carcinoma, chronic lymphocytic thyroiditis
Histiocytosis X
Kikuchi disease
Benign sinus histiocytosis
Angioimmunoblastic or immunoblastic lymphadenopathy
Chronic pseudolymphomatous lymphadenopathy (chronic benign lymphadenopathy)

Immunodeficiency syndromes and phagocytic dysfunction causing lymphadenitis are as follows:

Chronic granulomatous disease of childhood
Acquired immunodeficiency syndrome
Hyperimmunoglobulin E (Job) syndrome

Metabolic and storage diseases causing lymphadenitis are as follows:

Gaucher disease
Niemann-Pick disease
Cystinosis

Hematopoietic diseases causing lymphadenitis are as follows:

Sickle cell anemia
Thalassemia
Congenital hemolytic anemia
Autoimmune hemolytic anemia

Miscellaneous disorders causing lymphadenitis are as follows:

Kawasaki disease
PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis) syndrome
Sarcoidosis
Castleman disease (also known as benign giant lymph node hyperplasia)

Medications causing lymphadenitis are as follows:

Mesantoin – most commonly causes cervical lymphadenitis
Hydantoin - Generalized lymphadenopathy

REGIONAL LYMPHADENITIS

In a patient with regional lymphadenitis, knowledge of lymphatic drainage patterns and pathologic processes most likely to affect these areas can facilitate diagnostic investigation.

Cervical lymph nodes

Cervical lymph nodes receive lymphatic drainage from the head, neck, and oropharyngeal cavities.

Infections associated with cervical lymph nodes are as follows:

Skin and soft tissue infections of the face
Dental abscesses
Otitis externa
Bacterial pharyngitis
Cytomegalovirus
Adenovirus infection
Rubella
Toxoplasmosis

Malignancies associated with cervical lymph nodes are as follows:

Hodgkin lymphoma
Non-Hodgkin lymphomas
Squamous cell carcinomas of nasopharyngeal or laryngeal structures

BIOPSY

Choice of biopsy: FNAC versus Excisional biopsy

Fine-needle aspiration and cytology (FNAC) is an alternative to excisional biopsy.

Advantages of excisional biopsy:

larger tissue mass to examine
can examine the entire abnormal lymph node

Disadvantages of FNAC:

FNAC often yields a high number of non diagnostic results,
because of the small amount of tissue obtained and
the inability to examine the architecture of the lymph node.
There may be some risk of sinus tract formation, depending on the underlying pathology.

Lymph node biopsy is performed by the Pathology MO under local anaesthesia. The specimen is sent to the Pathology laboratory for processing and examination.

Pathology reports should be available within a week of performing FNAC or excisional biopsy.

Incision and drainage is the treatment for lymphadenitis with abscess formation.

For atypical mycobacterial lymphadenitis, neither incision and drainage nor FNA should be performed as either of these may increase the risk of fistula formation and drainage.

CANCEROUS OR NOT?

Is it cancer or not? Is it benign or malignant?

Physical examination findings suggestive of malignancy are as follows:

Firm
Hard
Fixed
Non tender

Physical examination findings suggestive of infection are as follows:

Soft
Fluctuant
Tender
Overlying erythema or streaking

External links:

Lymphadenopathy
http://emedicine.medscape.com/article/956340-overview
http://www.aafp.org/afp/1998/1015/p1313.html
http://www.msdmanuals.com/professional/cardiovascular-disorders/lymphatic-disorders/lymphadenopathy
https://en.wikipedia.org/wiki/Lymphadenopathy

Lymphadenitis
http://emedicine.medscape.com/article/960858-overview

Tuesday, 15 March 2016

Insulin

Jugular Venous Pressure (JVP)

Friday, 4 March 2016

Vitamin B

Generally, vitamin B helps a person to eat, especially in patients who have recovered from conditions where they have suffered loss of appetite (LOA).

Vitamin B is prescribed in various forms, for certain conditions, among them poor fingernails in children after recovery from a severe illness, hair loss in children after ringworm infection of the scalp, pain in the bones and tissues in post-menopausal women after a fall - to aid nerve development, and anemia in menstruating ladies.

Vitbion is prescribed for bone pain in elderly ladies who suffered a fall and have pain in the affected area or have whole body pain from osteoporosis. This is a bright orange tablet packed in 10's on an aluminium foil.

Vitbion Forte Tablet
Manufactured by Dynapharm (M) Sdn Bhd
Malaysian code: MAL19920011X
Active ingredients:
Thiamine HCl (Vit B1 100 mg
Pyridoxine HCl (Vit B6) 200 mg
Cyanocobalamin (Vit B12) 200 mcg

Vitamin B tablets look similar to vitamin C tablets, but vitamin B tablets are much larger and flatter at the edge compared to vitamin C tablets.

Vitamin C and B tablets can be easily confused in the elderly with poor eyesight. Feeling the tablets and knowing how to differentiate them by touch is therefore important for the elderly.

Vitamin C is bright red, smaller and rounder with a smooth polished feel. Vitamin C is packed in small plastic bags that need to be snipped to create a small opening for dispensing.

External links
https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
https://en.wikipedia.org/wiki/B_vitamins
http://www.naturemade.com/resource-center/articles-and-videos/