2. • Senior Consultant …Obs/Gyn.
• Egypt..MOH..Head of Obs/ Gyn department…Damietta General
Hospital.
• Former Head of Obs/Gyn department KMMPH (Maternity
hospital) –KSA.
• Former Head of Obs/Gyn department Khamis Civil hospital
(general hospital) –KSA.
Dr. Mostafa Darweish
2Dr Mostafa Darweish
3. • Cervical cancer
• Worldwide, cervical cancer is the second
most common female malignancy, with only
breast cancer occurring more frequently.
•
• In the UK, cervical cancer is the third most
common gynaecological malignancy after
ovarian and endometrial cancer.
3Dr Mostafa Darweish
4. • Cervical cancer
• The incidence and mortality of cervical
cancer has fallen significantly since the
introduction of the NHS Cervical Screening
Programme (NHSCSP) in 1988.
• Incidence rates decreased by 49% from their
peak in 1985–1987 (at 16.3 per 100 000
women) to the lowest rate in 2002–2004 (at
8.4 per 100 000 women) and have since
remained stable.
4Dr Mostafa Darweish
6. • Normal Cervix
• - 1-Glandular epithelium/ectropion (often visible on ectocervix(
3-New squamocolumnar junction
4-Original squamo-columnar junction (not visible with naked eye(
5-Transformation zone
2-External OS (visible with naked eye(
6Dr Mostafa Darweish
7. • Squamo-Columnar Junction (SCJ):
• The junction between ectocervix and endocervix.
• From late fetal life to the menopause the position of this
junction changes.
• Morphologically there are two types of SCJ:
• The original SCJ is the border where the original
squamous epithelium meets the outermost limit of the
developing TZ.
• The present (new) SCJ is the innermost border where the
maturing squamous metaplasia meets the columnar
epithelium
7Dr Mostafa Darweish
9. Transformation Zone (TZ)
• It is the area of actively maturing epithelium
between the present (new) SCJ and the original
squamous epithelium.
• It is composed of intermingling of squamous and
columnar epithelium, squamous metaplasia,
islands of columnar epithelium, gland openings
and nabothian cysts may be identified.
• The precise location of TZ varies in relation to exo-
and endocervix
9Dr Mostafa Darweish
10. • TZ is the site of greatest epith activity and the
great majority of carcinoma of the cervix arise
from this artea.
• TZ with gland opening, sq.metaplasia, columnar
epithelium.
Transformation Zone (TZ)
10Dr Mostafa Darweish
13. • Preinvasive disease of the female lower
genital tract encompasses a spectrum of
intraepithelial neoplasia of the cervix, vulva
and vagina.
• These changes are referred to as cervical,
vulval and vaginal intraepithelial neoplasia
(CIN, VIN and VAIN, respectively).
13Dr Mostafa Darweish
14. • The term cervical intraepithelial
neoplasia (CIN) refers to a spectrum of
abnormalities of the surface epithelium.
• The spectrum includes changes in the TZ
ranging from CIN I (mild dysplasia) to CIS
(carcinoma in situ).
14Dr Mostafa Darweish
15. • Pathology of the cervix –
• Histology ..
• Cervical intraepithelial neoplasia (CIN)
15Dr Mostafa Darweish
17. • Cytologic aberrations seen in CIN
include: hyperchromaticity, abnormal
chromatin distribution, increased
nuclear to cytoplasmic ratio and nuclear
pleomorphisim.
• These abnormalities may be seen in
exofoliated cells in a Pap smear.
17Dr Mostafa Darweish
18. • Cervical Cancer Screening Program
• Cervical cancer screening detects
preinvasive neoplasia, thereby making
treatment possible before the disease
becomes invasive.
• Screening is performed using cervical
cytology (Pap test), or a human
papillomavirus (HPV) test, or a combination
of the two tests.
18Dr Mostafa Darweish
19. • In the UK, the NHS Cervical Screening Programme
screens:
• Women between 25 and 49 years every 3 years
• Women between 49 and 64 years every 5 years.
• Women less than 25 years of age are generally not
screened, as changes in the cervix in this age group will
usually resolve and detection of these changes may lead
to overtreatment with its consequences. Furthermore,
screening at a younger age will detect a high degree of
lowgrade smears, which would significantly increase
workload.
19Dr Mostafa Darweish
20. Pap Test
• The Pap test was introduced as a cervical screening
test in 1943 by George Papanicolaou for whom it is
named.
• It is a way to examine cells collected from the
cervix and vagina.
• This test can show the presence of infection,
inflammation, abnormal cells, or cancer.
20Dr Mostafa Darweish
21. • A Pap test is simple, quick, painless, while a
woman lies on an examination table
• Insert a speculum .
21Dr Mostafa Darweish
Pap Test
23. An optimal cervical specimen includes sampling of the
squamous epithelium (ectocervix) and columnar epithelium
(endocervix) and in particular the transformation zone, where
the majority of cervical neoplasias arise.
23Dr Mostafa Darweish
Spatula
Collecting the Pap Smear
25. • Plastic Broom Papette
Collecting the Pap Smear
25Dr Mostafa Darweish
26. Spread the material collected on the spatula /
cervix brush evenly over the slide with a
painting action and single smooth stroke motion
using both sides. 26Dr Mostafa Darweish
29. • Most centres now use liquid-based cytology to detect
cervical disease.
• In liquid-based cytology, cells are removed by a plastic
broom and suspended in transport medium before the
medium is spun and the cells transferred to a glass slide
to be examined.
Liquid-based cytology (LBC(
29Dr Mostafa Darweish
30. • liquid-based cytology :
• Liquid-based cytology lowers the number of
unsatisfactory smears significantly and may
increase the reported cases of dyskaryosis.
•
• There is also the potential for the transport
medium to be used for HPV testing and in the
detection of other sexually transmitted diseases.
30Dr Mostafa Darweish
32. • The FDA in 2003 approved a combination Pap/HPV DNA
test for primary screening.
• Current recommend use in women over 30.
• Of more than 70 types of HPV, more than 35 are
associated with “ano-genital” disease and 20 or more are
associated with cancer.
• The most common HPV types detected in cervical lesions
are those classified as high-risk HPV types, including
types,16,18,45, and 56, found in 77% of HSIL(CIN II-III)
and in 84% of invasive cancer.
HPV as screening tool
32Dr Mostafa Darweish
33. • Human papillomavirus
• Features associated with HPV include:
• koilocytosis (vacuolated cells).
• Hyperkeratosis.
• Multi-nucleation.
33Dr Mostafa Darweish
34. Which patient should have Pap test
• Women who are or have been sexually active
should have Pap tests and physical examination
regularly every 3 years.
• Women who have had hysterectomy for
treatment of a precancerous or cancerous
condition should have the end of the vaginal
canal sampled for abnormal changes.
34Dr Mostafa Darweish
35. Timing of Pap test be done?
• A woman should have this test when she is not
menstruating; the best time is between 10 and 20
days after the first day of the menstrual period.
• For about 2 days before a Pap test, she should
avoid douching, or using vaginal medicines or
spermicidal foams, creams or jellies. These may
wash away or hide abnormal cells.
35Dr Mostafa Darweish
36. • Dysplasia is a term used to describe abnormal
cells.
• Cervical cells undergo a series of changes in
their appearance.
• It is classified into mild, moderate and severe
depending on how abnormal the cells appear.
Terms to describe abnormal results
Pap test results
36Dr Mostafa Darweish
37. • Cervical Intraepithelial Neoplasia CIN
• Another term widely used to describe
abnormalities of surface epithelium.
• The term CIN along with a number (1 to 3),
describes how much of the cervix contains
abnormal cells.
• Carcinoma in situ(CIS) describes a pre-invasive
cancer that involves only the surface cells.
Terms
37Dr Mostafa Darweish
38. • Squamous Intra-epithelial Lesion (SIL)
• An intraepithelial lesion means that the
abnormal cells are present only in the surface
layers of the cells.
• SIL may be described as low-grade(early
changes in size, shape and number of cells) or
high-grade (a large number of precancerous
cells the look very different from normal cells).
Terms
38Dr Mostafa Darweish
39. • Mild dysplasia may be also classified as CIN I or
low-grade SIL
• Moderate dysplasia may also be classified as CIN
II or high-grade SIL.
• Severe dysplasia may also be classified as CIN III
or high-grade SIL
• Carcinoma in situ may also be classified as CIN III
or high-grade SIL.
SUMMARY Terms to describe abnormal results
39Dr Mostafa Darweish
41. • CIN 1 = INFECTIONS= Treat And Repeat
• Trichomonas vaginalis ( Metronidazole 400mg tds and
Doxycyline 100mg bd for 1 week).
• Fungal infection: Antifungal
• Bacterial vaginosis (Metronidazole, Clindamycin)
• Actinomyces species: Penicillin
• Herpes simplex: Acyclovir.
• Repeat smear in 6-8 weeks, if persistent in 3 occasion,
refer for colposcopy.
• ATROPHIC SMEAR: Local oestrogen cream/tab (1 gm
nighty for 2 weeks then twice weekly) 6-8 weeks and
repeat pap smear in 3-4 months.
Management of CIN
41Dr Mostafa Darweish
42. • CIN1 probably does not require immediate
treatment, as it has a much lower malignant
potential than the higher grades.
• In general persistence of CIN 1 is regarded as
indication for eradication.
• CIN 2 & 3 are usually treated without undue
delay (most common method include LLETZ).
Management of CIN
42Dr Mostafa Darweish
43. • Cervical glandular intraepithelial neoplasia (CGIN)
• The majority of cervical precancerous changes are
squamous in nature.
• However, abnormal glandular changes do occur.
• Cervical glandular intraepithelial neoplasia (CGIN)
describes premalignant glandular lesions of the
cervix. It is important to remember that the
cervical screening programme was developed to
detect premalignant changes in squamous
epithelium only.
• HPV 18 is mainly responsible for causation of CGIN.
43Dr Mostafa Darweish
44. • Cervical glandular intraepithelial neoplasia (CGIN)
• It occurs in approximately one per 2000 smears
• It occurs in an older age group compared with CIN
• Colposcopic assessment is essential.
• In cases of glandular abnormalities in smear the
woman must be referred to colposcopy urgently
within two weeks of referral.
• Treatment should be by excisional biopsy (as
assessment of CGIN is difficult there is a lower
threshold for excisional biopsy).
44Dr Mostafa Darweish
45. • Cervical glandular intraepithelial neoplasia (CGIN)
• When CGIN is completely excised a test of cure
sample should be taken at 6 months after
treatment
• Simple hysterectomy might be considered for CGIN
if fertility is not required.
45Dr Mostafa Darweish
46. • Colposcopy is considered an integral instrument
for evaluation of patients with abnormal Pap
smears.
Colposcopy
46Dr Mostafa Darweish
47. • The colposcope is a binocular, low-magnification
(7x to 30x) microscope with light source which is
used to visualize the cervix, vagina and vulva.
• The goal in the evaluation of the lesions is to
exclude the possibility of malignancy.
• Satisfactory colposcpies are those in which the
lesion and the SCJ can be seen in entirety.
Colposcope
47Dr Mostafa Darweish
48. • Colposcopy mainly evaluates changes in the
terminal vascular network of the cervix that
reflect the biochemical and metabolic
changes in the tissues.
• The presence of negative colposcopic
finding despite persistent abnormal smears
calls for dignostic conisation.
Colposcope
48Dr Mostafa Darweish
49. Methods of Colposcopic Examination
• The cervix and vagina are first examined at
magnification of 7x or 10x following which
excess mucus is removed from the cervix.
• Acetic acid 3% to 5% is applied by cotton swab.
• Abnormal epithelium appear as thick white
(acteo-white).
• Schiller iodine test may be applied.
• Saline Technique.
49Dr Mostafa Darweish
50. Diagnostic criteria for Colposcopy
• In its simplest form colposcopy is the recognition
of aceto-white epithelium.
• Acetic acid causes some swelling of epithelium
particularly columnar epithelium and abnormal
epithelium.
50Dr Mostafa Darweish
51. Acetic Acid
• Acetic acid 3%-5% dissolves mucous and
accentuates atypical areas (white epithelium,
punctation, mosiac and atypical vessels) by
inducing intracellular dehydration and
coagulation of protein.
• This effect peaks approximately 2 minutes after
application and fades within 5 minutes.
• Therfore, repeated applications is rquired.
51Dr Mostafa Darweish
52. Lugol’s Iodine
• Lugol’s solution is composed of Iodine and
potassium iodide in water.
• It stains the glycogen in mature squamous
epithelium a dark brown color.
• Consequently, areas devoid of glycogen such as
immature squamous epithelium, columnar
epithelium, erosion and neoplasia will be non-
staining.
• Non-staining is called Schiller’s positive.
COLPOSCOPY
52Dr Mostafa Darweish
53. The Saline Technique
• This depends entirely on the visualization of
various vessel patterns.
• After exposing the cervix saline is used to
remove mucous and then a green filter and high
magnification is used.
• In this way the red capillaries appear “darked”
and stand out more clearly.
COLPOSCOPY
53Dr Mostafa Darweish
54. Vascular Abnormality
• Atypical vessels: this vascular growth is not symmetric and is
often associated with progressively smaller blood vessels.
COLPOSCOPY
54Dr Mostafa Darweish
55. • Mosaic : A vascular change of “interconnecting” vessels
resulting in “cobble-stone” or honey-comb surface.
• This is usually seen with CIN and mandates biopsy.
Vascular Abnormality
COLPOSCOPY
55Dr Mostafa Darweish
56. • Punctation
• It is a zone of red dots representing stromal papillae and
blood vessel loops reaching to the surface epithelium.
• When this pattern is identified biopsy is indicated.
Vascular Abnormality
COLPOSCOPY
56Dr Mostafa Darweish
57. Biopsy Forceps
• Used for punch biopsy from abnormal area
COLPOSCOPY
57Dr Mostafa Darweish
58. • SUMMARY
• Colposcopy referral guidelines:
• Women should be referred for colposcopy if they have:
• Three consecutive inadequate smears
• Borderline nuclear abnormality (squamous or glandular) with
highrisk
• HPV positive
• One mild dyskaryosis with high risk
• HPV positive
• One moderate dyskaryosis
• One severe dyskaryosis
• One smear with possibility of invasion
• One smear with possibility of glandular neoplasia.
• After treatment (by loop or thermocoagulation) if highrisk
• HPV positive (irrespective of cervical smear result). 58Dr Mostafa Darweish
59. • Approximately 1-3% of Pap smears will read as
abnormal.
• The standard evaluation of an abnormal Pap
smear is colposcopy and biopsies.
• Endocervical curettage (ECC) at the time of
colposcopy allows evaluation of cells from the
endocervicl canal.
• Biopsy should confirm the Pap smear abnormality
and then appropriate treatment can be applied.
Management of Abnormal Pap Smear
59Dr Mostafa Darweish
60. Diagnostic Biopsy
• To confirm the diagnosis
• To D.D. preinvasive and invasive carcinoma
60Dr Mostafa Darweish
61. Diagnostic Biopsy
• Types of cevical biopsy:
• Colposcopically- directed biopsy
• Biopsy from the susp. area including part of the
healthy tissue.
• Multiple punch biopsy from 4 quadrants
• Cone biopsy.
• NB- Colposcopically- directed biopsies have
eliminaterd the need for the blind biopsies
61Dr Mostafa Darweish
62. Cone biopsy
• Indications:
• Negative colposcopy with positive smear
• Entire lesion is not seen
• Adenocarcinoma in situ
• Positive ECC (Endocervical curettage)
62Dr Mostafa Darweish
63. Cone Biopsy
• The most commonly used cone biopsy include:
• Cold-knife cone.
• Laser excisional cone.
• Loop Electrosurgical Excision Procedure (LEEP) cone.
63Dr Mostafa Darweish
64. Cold-Knife Cone
• It is simply removal of a cone of tissue
with a scalpel.
• Usually performed under anaesthesia
• It delivers a perfect specimen for
patological examination.
64Dr Mostafa Darweish
66. • Precautions Before the use of ablative therapy:
• 1. No Evidence of invasive cancer on Pap smear,
cervical biopsy or colposcopy.
• 2. No evidence of an adenomatous lesion
(adenocarcinoma in situ or adenocarcinoma).
• 3. Satisfactory colposcopy i.e. complete
visualization of the lesion and TZ.
• 4. Endocervical curettage negative for CIN
• 5. No discrepancy between Pap smear and
biopsy.
• 6. Patients is complaint with follow-up
66Dr Mostafa Darweish
68. Ablative Therapy
• These techniques remove up to 8 mm in
tissue depth and up to 30 mm in diameter,
including the transformation zone.
• When applied correctly have excellent
success rate (90-95%).
68Dr Mostafa Darweish
71. Cryo-therapy
• Cryo-therapy is freezing the cervix to destroy the
abnormal cells.
• It has minimal discomfort, moderate cervical distortion,
and minimal expense.
• The technique involves the use of a gas with a boiling
point in the cryptogenic range to freeze the cervix for 3
to 6 minutes.
• Tissue destruction occurs to a depth of 8 mm when an
ice ball extending 5 mm beyond the lesion is created.
• The disadvantage is the remainder of the lesion cannot
be examined by pathologist to absoultly sure a worse
lesion was not present. 71Dr Mostafa Darweish
72. LASER
• This involves the use of carbon dioxide laser to
evaporate tissue.
• The laser can be precisely controlled and is used
in conjunction with a colposcope or operating
microscope to destroy tissue to a depth of 8 mm.
• This technique provides no specimen for
pathologic diagnosis.
72Dr Mostafa Darweish
73. • It is indicated when patient is not
complaint with follow-up and has
completed her family.
HYSTERECTOMY
73Dr Mostafa Darweish
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
"Nosocomial" comes from two Greek words --disease contracted by a patent while under medical care.
Endogenous infections are those caused by microorganisms already part of the host flora ("normal flora" of the skin, nose, oral cavity, gastrointestinal tract, etc.) while exogenous infections are those caused by microorganisms obtained from animate or inanimate sources within the hospital.
