DEC (diethylcarbamazine) provocation test is used in the diagnosis of lymphatic filariasis
The usual method for confirming filariasis is by demonstrating microfilariae in night blood specimens ( due to the nocturnal periodicity)
In case it is not possible to obtain night blood specimens, DEC provocation test can be done
In this, 50-100 mg of DEC is given to a patient and a blood sample is taken 30-45 minutes later for looking for the presence of microfilariae
DEC is a drug used in the treatment of filariasis and it flushes out the microfilariae into the …

Histoplasma capsulatum – a dimorphic fungus

(Click on the image to view an enlarged version)

Fungi which exist in 2 separate morphological forms depending of environmental temperature

Yeast form within the body or in cultures at 37C
in the soil or in cultures at 22C

Many fungi causing systemic infections are dimorphic fungi

Examples of dimorphic fungi:

Histoplasma capsulatum
Sporothrix schenckii
Blastomyces dermatitidis
Coccidioides immitis

Ancylostoma duodenale
Necator americanus

First identified in Italy
First identified in Texas, USA

Old world hookworm
New world hookworm

Larger (male 8-11mm)
Smaller (male 7-9mm)

Anterior end bent in same direction of general curvature of body
Anterior end bent in opposite direction of general curvature of body

Prominent buccal capsule with 2 pairs of teeth
Smaller buccal capsule with 2 pairs of semilunar cutting plates

Vulva opens at junction of middle and posterior 1/3
Vulva opens a …

Extended spectrum beta lactamases (ESBLs) are enzymes that mediate resistance to extended-spectrum or third generation cephalosporins like ceftazidime, cefotaxime, and ceftriaxone and monobactams like aztreonam. ESBLs do not affect cephamycins like cefoxitin and cefotetan or carbapenems like meropenem or imipenem.

WHO has revised the pandemic alert for swine influenza to phase 5 on 29th April, 2009. US government site for authentic and updated information on flu pandemics is available at www.pandemicflu.gov. Phase 5 alert means that a pandemic is imminent. The virus strain causing swine influenza is H1N1 while the earlier avian flu pandemic was caused by the virus strain H5N1. The Director General of World Health Organization (WHO) Dr. Margaret Chan feels that the preparedness measures taken during the H5N1 avian influenza threat were an investment from which we …

Swine Influenza A outbreak has started in March, 2009 in Mexico. The number of suspected cases has increased to about 2000 while the death toll is increasing. Confirmed cases has been reported from the United States, Spain, Scotland and Canada. World Health Organization has increased the pandemic alert level from 3 to phase 4, meaning that “that the likelihood of a pandemic has increased, but not that a pandemic is inevitable”. Human to human transmission has evolved as cases without any contact with swine what so ever have occurred.
Swine Influenza …

It is a small gram negative bacillus.
 

Haemophilus influenzae in blood agar
Haemophilus influenzae meningitis

Term referring to Mycoplasma pneumoniae.
Eaton in 1944 isolated the causative agent of primary atypical pneumonia. It had the capability to pass through bacterial filters and hence was considered to be a virus which was named Eaton agent. Later it was found out that Eaton agent was a bacteria and was named Mycoplasma pneumoniae.

Causative organism – Mycoplasma pneumoniae
Also called primary atypical pneumonia
Incubation period – 1-3 weeks
Gradual onset
usually tracheobronchitis, 1/3 develop pneumonia
usually lasts for 1-2 weeks
Mode of spread – droplet spread
favoured by close contact (famalies,  military recruits)
mycoplasma may persist in throat for 2 or more months after recovery

 
Clinical manifestations

Fever
headache
malaise
sorethroat
paroxysmal cough
blood tinged sputum

Findings on physical examination are minimal
radiography shows patchy consolidation of lower lobes – starting at hilum, fanning to periphery

 
Complications

myringitis bullosa, otitis – common
rashes
meningitis
encephalitis
hemolytic anemia

 
Lab diagnosis:

Pleomorphism refers to the existance of 2 or more structural forms in the life cycle of an organism. 
In bacteriology, it refers to the variation in the structural forms exhibited by a bacteria. Eg: Mycoplasma is a highly pleomorphic bacteria.