Melioidosis is caused by the bacterium Burkholderia pseudomallei. It is endemic in Southeast Asia and Northern Australia. People at highest risk include those with diabetes, renal or liver disease, or who are immunosuppressed. The bacteria can cause localized skin infections, pneumonia, or disseminated disease affecting multiple organs. Symptoms range from skin ulcers to respiratory distress. Diagnosis involves culture of the bacteria from blood or infected tissues. Treatment requires initial intravenous antibiotics such as meropenem followed by long-term oral eradication therapy with co-trimoxazole and doxycycline to prevent relapse.

1. Melioidosis

2. WHAT IS MELIOIDOSIS?
• Melioidosis, also known as Whitmore disease, is caused by the
bacterium Burkholderia pseudomallei (a motile, aerobic, non–spore-
forming bacillus).
• It is clinically and pathologically similar to glanders, although the
epidemiology differs.
• The bacteria thrive in tropical climates. The disease is endemic in
Southeast Asia and Australia, and is also found in the Middle East,
India, and China

3. WHO ARE AT RISK
Farming has been shown to strongly associated with incident cases
• Wet season  heavy rainfall,high humidity and temp
the major risk factors are :
• Diabetes
• Liver disease
• Renal disease
• Excessive alcohol consumption
• Cancer or another immune-suppressing condition not related to HIV
• Chronic lung disease (such as cystic fibrosis, chronic obstructive
pulmonary disease, and bronchiectasis)

4. Possible complications of these diseases include the following:
• Septicemia
• Osteomyelitis
• Meningitis
• Brain, lung, liver, or splenic abscess
However, even though these factors do increase the risk of contracting
melioidosis, cases of infection can still occur in healthy adults and
children occasionally.

5. Besides humans, many animal species are susceptible to
melioidosis, including:
• Sheep
• Goats
• Swine
• Horses
• Cats
• Dogs
• Cattle

6. PATHOGENESIS
• Melioidosis is an infectious disease caused by B pseudomallei
• The organism is distributed widely in the soil and water of the tropics.
It is spread to humans through direct contact with a contaminated
source, especially during the rainy season.
• The disease usually occurs in especially among those who have
chronic comorbidities such as diabetes, alcoholism,
immunosuppression, and renal failure
• The incubation period in naturally acquired infections can vary from
days to months to years.

7. PATHOGENESIS
The disease can manifest as Acute, Sub acute, and Chronic disease

8. Localized form
• Bacteria enter the skin through a laceration or abrasion, and a local
infection with ulceration develops.
• The incubation period is 1-5 days.
• Swollen lymph glands may develop.
• Bacteria that enter the host through mucous membranes can cause
increased mucus production in the affected areas.

9. Pulmonary form
• When bacteria are aerosolized and enter the respiratory tract via
inhalation or hematogenous spread, pulmonary infections may
develop.
• Pneumonia, pulmonary abscesses, and pleural effusions can occur.
The incubation period is 10-14 days.
• With inhalational melioidosis, cutaneous abscesses may develop and
take months to appear.

10. Bacteremia/Septicemia
• bacteremia is observed with chronically ill patients (eg, patients with
HIV/diabetes).
• Patients often presents with a history of fever with no evidence of focus of
infection
• The onset may be abrupt and usually rapidly progresses to disseminated
bacteremia ,multi organ involvement and septicaemic shock
• They develop respiratory distress, headaches, fever, diarrhea, pus-filled
lesions on the skin, and abscesses throughout the body.
• Septicemia may be overwhelming, with a 90% fatality rate and death
occurring within 24-48 hours.

11. Chronic form
• The chronic form involves multiple abscesses, which may affect the
liver, spleen, skin, or muscles.
• in addition to this chronic form, can become reactive many years after
the primary infection
• long-standing suppurative focal abscesses with or without fever and is
associated with a good prognosis

12. Progression of infection
• The infection starts with non specific lesion at the inoculum, where
there can be break in the skin.
• Lead to septicemia
• Most common form is pulmonary infection
• Can lead to suppurative infection and bacteremia

13. Clinical Manifestation
Bloodstream Infection:
• Fever
• Headache
• Respiratory distress
• Abdominal discomfort
• Joint pain
• Disorientation
Disseminated Infection:
• Fever
• Weight loss
• Stomach or chest pain
• Muscle or joint pain
• Headache
• Seizures

14. LABORATORY INVESTIGATIONS
• Routine tests : FBC, UFEME, renal and liver functions, blood sugar
• Blood cultures 2X ( at 2 different sites at the same time before
antibiotic given)
• Urine culture
• Cultures from abscess, joint aspirate, CSF, sputum or throat swab
where indicated
• PCR for blood, body secretion and urine may also be indicated

15. • Blood culture results for B pseudomallei often positive and positive
urine cultures can indicate prostatitis or renal abscesses.
• In septicemic melioidosis, blood culture results may be negative until
just before death.
• Polymerase chain reaction (PCR) assays are rapid and specific but may
be less sensitive than cultures.

16. RADIOLOGICAL INVESTIGATIONS
• Chest X-ray
• USG abdomen
• CT Scan where indicated such as for cerebral abscess. For the purpose
of the registry and research, it is required that an abdominal CT scan
be done to diagnose prostatic abscess.

17. Serology
Serological test may be helpful in diagnosis of melioidosis. There are
few serological tests available like
• Indirect Haemagglutination Test (IHAT)
• Immunofluorescent Antibody Test (IFAT)
• IgG and IgM ELISA
• Rapid Immunochromatographic (IC) test for IgG and IgM
In endemic area, the most rapid, sensitive and specific for current
infection is IFAT.
Interpretation of IFAT result: Positive : > 1:80 (in endemic area if patient
is asymptomatic, a titre of as high as 1:160 may not be significant but
patient need to be followed up

18. • ANTIBIOTICS
• INTENSIVE THERAPY
• Life threatening melioidosis
• IV Meropenem (25mg/kg/dose; usual dose for adult: 1 gm TDS) for at least 2 weeks. May
substitute Meropenem with Imipenem (50mg/kg/day; usual adult dose 1gm tds). 19
• May add an adjunct antibiotic; Co-trimoxazole (TrimethoprimSulphamethoxazole) 3-4 tab bd
+ Folic acid 5 mg daily. To consider G-CSF within 72 hours of admission
• Localized superficial melioidosis
• Oral Augmentin ( Amoxycillin/Clavulanate) 2 tab (500/125) tds for 12-20 weeks.
• Others melioidosis
• IV Ceftazidime (100 mg/kg a day; usual dose for adult, 2 gm TDS) • To consider G-CSF within
72 hours of admission

19. • ERADICATION THERAPY
• Oral Co-trimoxazole (Trimethoprim 8mg/kg/day and Sulfamethoxazole
40mg/kg/day) and Doxycycline (4 mg/kg/day in 2 divided doses per day)
(Usual dose 2-4 tab Cotrimoxazole BD and Doxycycline 100mg BD) are the
standard oral combination regimen and should be administered for a total of
20 weeks.
OR
• Augmentin (Amoxycillin/Clavulanate 2 tab) tds, is an alternative and can be
used in pregnant women and those allergic to Co-trimoxazole (for the same
duration).

20. Thank You