Aspergillus and penicillium- fungi causing respiratory infections. These fungi are opportunistic fungi. Microbiology and lab diagnosis included

1. ASPERGILLUS
PENICILLIUM

2. LESSON
PLAN
Introduction to Aspergillosis
Pathogenesis
Clinical features
Lab diagnosis
Treatment
Introduction to Penicillium
Clinical features
Lab diagnosis

3. INTRODUCTION
Aspergillus species are saprophytic molds found in
decaying organic matter worldwide.
Causes opportunistic and systemic fungal infection both in
immunocompromised and immunocompetent individuals.
More than 300 species, but nearly 35 are known to be
pathogenic.
Common species are A.fumigatus, A.flavus and A.niger
Pathogenic spp. grows both at 37ºC and 25ºC in mold
form.

4. PATHOGENESIS
ASPERGILLOSIS
Finally germinate and colonise.
Prevents phagocytosis with pulmonary alveolar macrophages.
Bypass the URT defense mechanism & reaches alveoli.
Inhalation of these airborne conidia.
Aspergillus forms chains of conidia.

5. s

6. CLINICAL FEATURES
PULMONARY ASPERGILLOSIS:
Allergic bronchopulmonary aspergillosis(ABPA):
• Forms fungal plugs and Provokes a hypersensitivity reaction :
Type 1 (asthma),Type 3(extrinsic alveolitis)or both.
• Breathlessness , fever and malaise and finally lung damage.
• Severe bronchial asthma
Aspergilloma(fungus ball):
• Fungal ball within an existing lung ….opacity on X rays due to
compact mass of fungus . Patients have massive,
haemoptysis.(**Monod’s sign/air crescent sign)

7. Invasive aspergillosis : Mainly in immunocompromised.
• Invasive sinusitis: Commonly by A.Flavus. Present as acute, chronic,
invasive and fulminant type
• Cerebral aspergillosis : Due to haematogenous spread
• Cardiac aspergillosis : Endocarditis, mainly after cardiac surgery
• Ocular and external ear aspergillosis
Cutaneous aspergillosis
• Nail bed infections

8. LAB
DIAGNOSIS
Sample collection:
• sputum, Bal fluid and
other samples.
Direct examination :
• KOH mount
• narrow septate hyaline
hyphae with acute
angle branching’’

9. H &E staining of tissue section

10. CULTURE
Sample inoculated on SDA(without cycloheximide) and incubated at 37 and 25⁰C.
CULTURE GROWTH
Smokey green yellowish green black
Velvety powdery powdery
A.Fumigatus A.flavus A.niger

11. Species identification
Lacto phenol
cotton blue
staining (LPCB)
is done from
the culture
growth.
conidiophore

12. Smokey green,velvety/powdery Uniseriate phialide
Aspergillus fumigatus

13. Greenish yellow Uniseriate/Biseriate phialide
Aspergillus flavus

14. Brownish black colonies Biseriate phialide
Aspergillus niger

15. OTHER TESTS
Antigen detection :
ELISA to detect
galactomannan for
early diagnosis
Antibody detection :
Useful in chronic cases.
Detection of
metabolites :
• G test : Detection of ᵦ 1-3 D
glucan.
• mannitol detection
Skin test: positive skin
test to various antigens

16. TREATMENT Azoles are the drug of choice. For
Ex: itraconazole, voriconazole etc.
Invasive aspergillosis is treated
with amphotericin B
For aspergilloma surgery can be
done.

17. PENICILLIUM
Penicillium name comes
from “penicillus” = brush
Now named as
Talaromyces.
Causes
Penicillosis/Talaromycosis
Ubiquitis in
nature……Grows on stale
food items.
Most common pathogenic
species is Penicillium
marneffii…….
which is a thermally
dimorphic fungus
• Causes opportunistic infections in
HIV-infected patients.
• Endemic in Thailand , Vietnam
and India(Manipur)

18. Pathogenesis
Reservoir of infection are the bamboo rats
Transmission by inhalation of conidia (mold form)
In lungs mold form is converted to yeast
Yeast form spreads via blood
spreads to reticuloendothelial system

19. Penicillium chrysogenum(P.notatum)

20. PENICILLIUM
MARNEFFI
• True pathogen
• Name P.marneffi was given in
honour of Dr Hubert Marneffe,
Director of Pasteur Institute
• Important opportunistic infection
in HIV infected individuals
• Thermally dimorphic
• Primary site of infection is
reticuloendothelial system

21. CLINICAL
FEATURES
SYSTEMIC INFECTION : Fever ,
weight loss,dyspnea
,lymphadenopathy and
hepatosplenomegaly
SKIN LESIONS : Umbilicated
;papular lesions similar to
that of molluscum
contagiosum

22. Skin lesions

23. LABORATORY
DIAGNOSIS
• Skin, bone marrow , respiratory samples
Sample collection :
• thin septate hyphae
Direct examination:
• Of tissue sections, skin scrapings , blood
smear-
• Oval yeast cells with central septation
Histopathological staining :

24. CULTURE: As dimorphic P.marneffii grows at two temperatures.
25⁰C
mold form
Rapid growing
, flat, granular
grey-green in center,
Brick red pigment
37⁰C
small yeast 2-
4 µm

25. mold form yeast form

26. LPCB mount of PENICILLIUM MARNEFII
Septate hyphae with branched conidiophores ,appear like broom/brush

27. • TREATMENT : Amphotericin B with itraconazole

28. THANK YOU