Macrolide (eg: Erythromycin)

Antibiotic for outpatient management of adult with CAP (Community Acquired Pneumonia)
-Cefuroxime (2nd G of Cephalosporins)
- and Macrolide (erythromycin)

Macrolide

The macrolides are a group of drugs (typically antibiotics) whose activity stems from the presence of a macrolide ring, a large macrocyclic lactone ring to which one or more deoxy sugars, usually cladinose and desosamine, may be attached. The lactone rings are usually 14, 15 or 16-membered. Macrolides belong to the polyketide class of natural products.

Common antibiotic macrolides
Azithromycin (Zithromax, Zitromax) - Unique, does not inhibit CYP3A4
Clarithromycin (Biaxin)
Dirithromycin (Dynabac)
Erythromycin
Roxithromycin (Rulid, Surlid,Roxid)

Developmental macrolides
Carbomycin A
Josamycin
Kitasamycin
Midecamicine/midecamicine acetate
Oleandomycin
Spiramycin
Troleandomycin
Tylosin/tylocine (Tylan)


Ketolides

Ketolides are a new class of antibiotics that are structurally related to the macrolides. They are used to fight respiratory tract infections caused by macrolide-resistant bacteria.
-Telithromycin (Ketek)
-Cethromycin
-Others include spiramycin (used for treating toxoplasmosis), ansamycin, oleandomycin, carbomycin and tylocine.


Non-antibiotic macrolides
-The drug tacrolimus (Prograf), which is used as an immunosuppressant, is also a macrolide. It has similar activity to cyclosporin.

Toxic macrolides
A variety of toxic macrolides produced by bacteria have been isolated and characterized, such as the mycolactones.

Uses
Antibiotic macrolides are used to treat infections such as respiratory tract and soft tissue infections. The antimicrobial spectrum of macrolides is slightly wider than that of penicillin, and therefore macrolides are a common substitute for patients with a penicillin allergy. Beta-hemolytic streptococci, pneumococci, staphylococci and enterococci are usually susceptible to macrolides. Unlike penicillin, macrolides have been shown to be effective against mycoplasma, mycobacteria, some rickettsia and chlamydia.

Mechanism of action
- inhibition of bacterial protein biosynthesis by binding reversibly to the subunit 50S of the bacterial ribosome, thereby inhibiting translocation of peptidyl tRNA. This action is mainly bacteriostatic, but can also be bactericidal in high concentrations.
- Macrolides tend to accumulate within leukocytes, and are therefore actually transported into the site of infection.

Resistance
- The primary means of bacterial resistance to macrolides occurs by post-transcriptional methylation of the 23S bacterial ribosomal RNA. This acquired resistance can be either plasmid-mediated or chromosomal, i.e through mutation, and results in cross-resistance to macrolides, lincosamides, and streptogramins (an MLS-resistant phenotype).
- Two other types of acquired resistance rarely seen include the production of drug-inactivating enzymes (esterases or kinases) as well as the production of active ATP-dependent efflux proteins that transport the drug outside of the cell.

Side effects
- A recent British Medical Journal article highlights that the combination of macrolides and statins (used for lowering cholesterol) is not advisable and can lead to debilitating myopathy.[citation needed] This is because macrolides are potent inhibitors of the cytochrome P450 system, particularly of CYP3A4. Macrolides also have a class effect of QT prolongation.

References
Macrolide Antibiotics: Chemistry, Biology, and Practice, 2nd Edition, Ed. Satoshi Omura, 2002, Academic Press

Disease affecting our Lung-- Pneumonia

Pneumonia is an illness of the lung and respiratory in which the alveoli (microscopic air-filled sacs of the lung responsible for absorbing oxygen from the atmosphere) become inflamed and flooded with fluid. Pneumonia can result from a variety of causes, including infection with bacteria, viruses, fungi, or parasites. Pneumonia may also occur from chemical or physical injury to the lungs, or indirectly due to another medical illness, such as lung cancer or alcohol abuse.

Typical symptoms associated with pneumonia include:

-cough

-chest pain

-fever

-difficulty breathing.

Diagnostic tools include x-rays and examination of the sputum.

Treatment depends on the cause of pneumonia; bacterial pneumonia is treated with antibiotics.

Symptoms

People with infectious pneumonia often have

- cough that produces greenish or yellow sputum(purulent sputum)

- high fever that may be accompanied by shaking chills.

- Shortness of breath (dyspnoea)

- pleuritic chest pain, (a sharp or stabbing pain, either felt or worse during deep breaths or coughs.)

They may:

- cough up blood

- experience headaches

- develop sweaty and clammy skin.

Other symptoms:

- loss of appetite

- fatigue

- blueness of the skin

- nausea

- vomiting

- joint pains or muscle aches.

For instance, pneumonia caused by Legionella may cause abdominal pain and diarrhea.

Pneumonia caused by tuberculosis or Pneumocystis may cause only weight loss and night sweats.

In elderly people the manifestations of pneumonia may not be typical. Instead, they may develop new or worsening confusion or may experience unsteadiness leading to falls.

Infants with pneumonia may have many of the symptoms above, but in many cases, they are simply sleepy or have decreased appetite.

Signs

Physical examination by a health care provider may reveal:

- fever or sometimes low body temperature

- increased respiratory rate

- confusion (in elderly)

- low blood pressure(hypotension)

- tachypnoea( fast breathing rate)

- fast heart rate

- low oxygen saturation

- cyanosis (blue-tinged skin) - require immediate attention.

Listening to the lungs with a stethoscope (auscultation) can reveal sign of consolidation:

- diminished lung expansion

- dull on percussion noted

- lack of normal breath sound (bronchial breath sound)

- tactile vocal fremitus/ vocal resonance

- presence of crackling sounds (rales)

- increased loudness of whispered speech (whispered pectoriloquy)

- pleural rub

Precipitating Factor

- Streptococcus pneumonia, often follows influenza @ parainfluenza viral infection.

- Hospitalized patient

- Alcohol excess

- cigarette smoking

- Bronchiectasis

- Broncial Obstruction (eg: patients with lung cancer)

- Immunosuppressed patient (eg: AIDS, cytotoxic agent)

- Intravenous Drug User (IVDU) -usually S.aureus

- Inhalation from oesophageal obstruction.

Risk Factor of Atherosclerosis

Atherosclerosis is a condition in which fatty material collects along the walls of arteries. This fatty material thickens, hardens, and may eventually block the arteries.

Atherosclerosis is a common disorder of the arteries. It occurs when fat, cholesterol, and other substances build up in the walls of arteries and form hard substances called plaque.
Eventually, the plaque deposits can make the artery less flexible. This makes it harder for blood to flow. If blood flow in the arteries leading to the heart is reduces, chest pain can occur. Plaques can also break apart, causing pieces of material to move through the artery. This is a common cause of heart attack and stroke. Blood clots can also form around the plaque deposits. Clots block blood flow. If the clot moves into the heart, lungs, or brain, it can cause a stroke, heart attack, or pulmonary embolism.

Risk factor:

Smoking
Diabetes
Obesity
High blood pressure
High-fat diet
Personal or family history of heart disease

Symptom.

Symptoms of atherosclerosis are usually not seen until blood flow becomes slowed or blocked.
Typical symptoms of atherosclerosis include chest pain if an artery to the heart is involved.
or leg pain when a leg artery is involved. Sometimes symptoms occur only with activity. In some people, however, they may occur at rest.

Complications:

Coronary Artery disease--
the blood supply to the heart is insufficient due to atherosclerosis/plaque in the arteries to the heart; a symptom is angina (chest pain)

Heart attack

TIA (Transient Ischaemic Attack) or Stroke--

Insufficient blood supply to the limbs (mainly the legs and feet) due to obstruction (claudication)
Damage to organ

Atherosclerosis and obstruction of bypass grafts

Abbreviation in Medicine

Abbreviations

---A---

a:

arteryAAA: abdominal aortic aneurysm

ACE: angiotensin converting enzyme

ACEi: ACE inhibitor

aka: also known as

APH: antepartum hemorrhage

APKD: adult polycystic kidney disease

ant: anterior

ARF: acute renal failure

AR: aortic regurgitation

AS: aortic stenosis

AnS: ankylosing spondylitis

ASD: atrial septal defect

ASIS: anterior superior iliac spine

ATN: acute tubular necrosis

AXR: abdominal x-ray

---B---

BCG: Mycobacterium bovis vaccine

BP: blood pressure

BPH: benign prostatic hypertrophy

---C---

CA: cancer

CABG: coronary artery bypass graft

CAD: cardiovascular artery disease

CF: cystic fibrosis

CHF: congestive heart failure

CMV: cytomegalovirus

CN: cranial nerve

CO: carbon monoxide

COPD: chronic obstructive pulmonary disease

CTR: cardiothoracic ratio

CXR: chest x-ray

---D---

D&C: dilatation and curettage.

Dx: diagnosis

DDx: differential diagnosis

DI: diabetes insipidus

DIC: disseminated intravascular coagulation

DIP: distal interphalangeal joint

DLE: discoid lupus erythematosus

DM: diabetes mellitus

Dr: doctor

DTP: diphtheria, tetanus, pertussis vaccine

DVT: deep vein thrombosis

dz: disease

---E---

EEG: electroencephalogram

ECG: electrocardiogram

EPO: erythropoetine

sp: especially

ESR: erythrocyte sedimentation rate

ext: external

---F---

FAS: fetal alcohol syndrome

FBC: full blood count

FET: forced expiration time

---G---

G6P: glucose-6-phosphate

GERD: gastro-esophageal reflux dz

GI: gastrointestinal

GIT: gastrointestinal tract

---H---

HiB: Haemophilus influenza

BHRT: hormone replacement therapy

HSV: Herpes simplex virus

HTN: hypertension

Hx: history

---I---

IBD: inflammatory bowel dz

ICP: intracranial pressure

IE: infective endocarditis

IHD: ischemic heart dz

inf: inferior

int: internal

IPPA: inspect, palpate, percuss, auscultate

IVC: inferior vena cava

---J---

---K---

---L---

Lt: left

LFT: liver function tests

LHF: left-sided heart failure

LLQ: left lower quadrant

LMN: lower motor neuron

LMNL: lower motor neuron lesion

LMP: last menstrual period

LUQ: left upper quadrant

LVF: left ventricular failure

---M---

MCP: metacarpophalangeal joint

min: minute

MMR: measles, mumps, rubella vaccine

MSU: midstream urine

MVP: mitral valve prolapse

MR: mitral regurgitation.

---N---

N2: nitrogen

NG tube: nasogastric tube

NSAID: non-steroidal anti-inflammatory drug

---O---

OA: osteoarthritis

OCP: oral contraceptive pill

OD: overdose

op: operation

OT/PT: occupational therapy, physiotherapy

---P---

PA: posterio-anterior

PAN: polyarterititis nodosa

PCOS: polycystic ovary syndrome

PCP: pneumocystis carinii

PDA: patent ductus arteriosus

PE: pulmonary embolism

pec: pectoralis

PEG: percutaneous endoscopic gastrostomy

PET: positron emission tomography

PIP: proximal interphalangeal joint

PMH: past medical history

PMS: pre-menstrual syndrome

post: posterior

PR: per rectum: examination, administration

PROM: premature rupture of membrane

PS: pulmonary stenosis

PSA: prostate-specific antigen

pt: patient

---Q---

---R---

R: right

RA: rheumatoid arthritis

RBBB: right bundle branch block

RBC: red blood cell

RCC: renal cell carcinoma

RHF: right-sided heart failure

RLQ: right lower quadrant

RMSF: rocky mountain spotted fever

ROS: review of systems

RTI: respiratory tract infection

RUQ: right upper quadrant

RVF: right ventricular failure

Rx /Tx: treatment

---S---

S1: first heart sound

S2: second heart sound

S3: third heart sound

S4: fouth heart sound

SAH: subarachnoid hemorrhage

SBE: subacute bacterial endocarditis

SCM: sternocleiodomastoid

s/e: side effect

SIJ: sacroiliac joint

SLE: systemic lupus erythematosus

SR: systems review

strep: Streptococcus

---T---

TB: tuberculosis

temp: temperature

TFT: thyroid function tests

TMJ: temporomandibular joint

---U---

UC: ulcerative colitis

U&E: urea and electrolytes

UMN: upper motor neuron

UMNL: upper motor neuron lesion

usu: usually

UTI: urinary tract infection

---V---

---W---

WBC: white blood cell

---X---

---Y---

yo: year-old

---Z---

---#---

1°: primary

2°: secondary

Hye, welcome to my blog!! aloohaaa =)

Hye, as mention, my name is Wan Mohd. Khalil Bin Wan Sapian Sori. Just call me khalil, alil, hale, wan, anything that suitable & comfortable to you, orait?

Mmmm...this is my 1st ever in my life, creating blog for all my beloved spectators who watches this site. so, hopefully you'll enjoy reading whatever i post here, okay?

Erm, maybe most of the time i'll share my medical knowledge to all of you so that both of us can learn, and gain some knowledge. win-win situation, remember that?

Well, that's all for the introduction. Thanks again, for watching =)

enjoy..

oppss..thanks for my dad, for introducing me bout this interesting stuff =)