This document discusses typhoid and syphilis. It begins by presenting a case scenario of a man experiencing abdominal pain, nausea, vomiting and fever who may have typhoid fever based on his recent consumption of undercooked eggs. It then provides details on the pathogenesis, clinical features, investigations and treatment of typhoid fever. The document also presents a case of a man with a penile sore and lymphadenopathy who is diagnosed with primary syphilis. It outlines the stages, signs and symptoms, histology, and management of syphilis.

1. INFECTIOUS
DISEASES
Dr. Jyothi Reshma S
Tutor
Dept of Pathology
TYPHOID, SYPHILIS

2. CASE SCENARIO - 01
• A 48 yr old man presents to casualty with 2
days of crampy abdominal pain, nausea,
vomiting, diarrhea and fever. He has not had
any blood in his stool. He denies contact with
anyone with similar symptoms recently. The
only food that he did not prepare himself in
the past week was a breakfast of eggs that he
had at a hotel the day before his symptoms
started.

3. • On examination, he is tired appearing, his
temp is 37.7⁰C, his heart rate is 95bpm, BP
110/60mm Hg. His mucous membranes
appear dry. His abdominal exam is notable for
diffuse tenderness but no palpable masses,
rebound or guarding. A rectal examination
reveals only bloodless watery stool.

4. ENTERIC FEVER
• SALMONELLA TYPHI (TYPHOID FEVER)
• SALMONELLA PARATYPHI (PARATYPHOID
FEVER)

5. MODE OF TRANSMISSION
Undercooked
poultry, eggs,
dairy products
or foods
prepared on
contaminated
work surfaces.

6. PATHOGENESIS
Invasion of lymphoid follicle and Peyer’s patches of small intestine
Invasion of bloodstream – bacteraemia – clinical features
Localisation in intestinal lymphoid tissue – mesenteric lymph nodes – liver
– gallbladder – spleen
Intestinal lesions – hemorrhagic lymphadenitis – hepatic parenchymal
necrosis – cholecystitis – splenic reactive hyperplasia

7. CLINICAL FEATURES
Chills, headache,
anorexia, weakness,
muscle aches
Fever,
lymphadenopathy,
hepatosplenomegaly
Rose spots –
maculopapular rash

8. GASTROENTERITIS
Colonize intestine
– terminal ileum
– nonbloody
watery diarrhea-
dehydration
Intestinal
bleeding,
ulceration,
perforation

9. SEPSIS
 Osteitis, arthritis, meningitis, orchitis
 Sickle cell anemia – salmonella
osteomyelitis – defective phagocytosis

10. CARRIER

11. MORPHOLOGY
 Terminal ileum
and colon –
peyer’s patches –
oval ulcers -
longitudinal
Base – sloughed
mucosa – black
Margin – raised

12. MICROSCOPY
 Hyperemia,
oedema, cellular
proliferation –
histiocytes,
lymphocytes,
plasma cells
P/S : leucopenia –
neutropenia,
relative
lymphocytosis

13. INVESTIGATIONS
• 1st week – blood culture
• 2nd week – antigen detection – Widal test
• 3rd week – stool culture
• 4th week – urine culture

14. TREATMENT
• Fluid correction
• Antibiotics – FQ – ciprofloxacin/
ceftriaxone/ azithromycin
• Sanitary measures
• Prophylaxis – vaccines

15. CASE SCENARIO - 02
• A 39-year-old male who presents to the STD
clinic because he’s had a sore on his penis for
one week. Last sexual exposure was three
weeks prior, without a condom. No history of
recent travel. Last HIV antibody test (two
months prior) was negative. Reports three
children with two different women.

16. • No oral, perianal, or extra-genital lesions.
Genital exam shows an uncircumcised penis
with a lesion on the ventral side near the
frenulum. Lesion is red, indurated, clean-
based, and non-tender. Two enlarged tender
right inguinal nodes, 1.5 cm x 1 cm. Scrotal
contents are without masses or tenderness.
No urethral discharge. No rashes on trunk,
palms, or soles. No alopecia. Neurologic exam
within normal limits

17. SYPHILIS
• TREPONEMA PALLIDUM
• Sexual intercourse resulting in lesions on glans penis, vulva, vagina
and cervix.
• Intimate person-to-person contact with lesions on lips, tongue or
fingers.
• Materno-foetal transmission – congenital syphilis
• Transfusion of infected blood.
• 3 clinical stages

18. • 3-6 weeks after initial
contact
• Primary chancre – site of
inoculation
• Regional non tender
lymphnode swelling
• Highly infectious
• Resolves - 4-6 wks- w/o
scar

19. Chancre – single, firm, ulcerated
painless lesion with a punched
out base and rolled edges

20. HISTOLOGY
• i) Dense infiltrate - plasma cells, lymphocytes,
macrophages.
• ii) Perivascular aggregation of mononuclear
cells - plasma cells (periarteritis and
obliterative endarteritis)
• iii) Proliferation of vascular endothelium.

21. SECONDARY SYPHILIS
• 6 wks after primary chancre resolution
• Stage of bacteraemia
• Systemic widespread rash
• Generalized lymphadenopathy
• Resolves – 6 wks – latent phase

22. Rash – small red maculopapular
- symmetrical distribution
- palms, soles, oral cavity

23. CONDYLOMA LATUM
• Painless, wart like lesion
• Moist areas – scrotum and vulva
• Highly contagious

24. Skin infection – areas of hair growth-
patchy bald spots and loss of eyebrows

25. LATENT SYPHILIS
• Asymptomatic – subclinical stage
• Serologically positive
• Early latent syphilis - 1 year after infection
• Late latent syphilis - longer than 1 year
• 25% - relapse - 2⁰
• 1/3rd - 3⁰ syphilis

26. TERTIARY SYPHILIS
• Over 6-40 years
• Slow inflammatory damage – organ tissue,
small blood vessels and nerve cells
• 3 categories : gummatous, cardiovascular,
neurosyphilis

27. GUMMATOUS SYPHILIS
• 3-10 years after 1⁰
infection – 15% untreated
• Gummas – rubbery gray
white – granulomas -
central coagulative
necrosis – plasma cell
infiltration
• Noninfectious – skin
(painless), bone (gnawing
pain), liver (hepar
lobatum)

28.  Central coagulative necrosis resembling caseation - less destructive -
outlines of necrosed cells
 Surrounding zone of palisaded macrophages - plasma cells, lymphocytes,
giant cells, fibroblasts.

29. Gumma (scar)
stained blue
Hepar lobatum

30. CARDIOVASCULAR SYPHILIS
• 10 years after 1⁰ infection – 10% untreated
• Aneurysm – ascending aorta , arch of aorta
• Aortitis - widening of the aorta - occasional linear
calcifications
• Inflammatory destruction – vasa vasorum – necrosis of
tunica media – narrowing of aortic annulus
• Aortic insufficiency (AR), coronary occlusion

31. • Intimal surface - pearly white thickenings -
fibrosis- wrinkled normal intima - tree bark
appearance.

32. NEUROSYPHILIS
• 8% untreated cases
• 5 presentations
Asymptomatic
neurosyphilis
Subacute
meningitis
Meningovascular
syphilis
General paresis of
insane Tabes dorsalis
CSF
high
lymphocyte
count & protein,
low glucose,
+ syphilis tests

33. • Tabes dorsalis: demyelination of the
 Posterior columns - vibratory,
proprioceptive sensations – ataxia
 Dorsal roots and dorsal ganglia - loss
of reflexes - loss of pain - temperature
sensation
 Neurosensory loss - Charcot joints
• Argyll Robertson pupil: a small,
irregular pupil that reacts to
accommodation but not to light–
tabes dorsalis and paresis

34. GENERAL PARESIS OF INSANE
• Progressive disease - nerve cells - brain- mental
deterioration – psychiatric symptoms
• PARESIS
Personality changes
Alteration of Affect
Hyperactive Reflexes
Alterations in Eye function (ARP)
Changes in Sensorium
Decreased Intellect
Slurred Speech

36. CONGENITAL SYPHILIS
• Still birth – spontaneous abortion – neonatal
death
• Fetus – infected mother - more than 16 weeks
gestation
• Early – w/i 2 years – snuffles –
lymphadenopathy – HSM – osteitis

37. Mucous patches

38. Snuffles - rhagades

39. LATE CONGENITAL SYPHILIS
Neurosyphilis
– eighth
nerve
deafness
Bone, teeth –
saddle nose –
saber shins –
hutchinson’s
teeth –
mulberry molars
Eye –corneal
inflammation
– interstitial
keratitis
HUTCHINSON’S TRIAD

40. Saddle nose
• Periosteal (outer
layer of bone)
inflammation
destroys the
cartilage - palate
and nasal septum -
sunken appearance

41. Saber shin
Inflammation - tibia - bowing

42. Hutchinson’s teeth
The upper central incisors are
widely spaced with a central
notch in each tooth

43. Mulberry molars
Molars have too many cusps

44. INVESTIGATION
• Direct visualisation – active stage -1⁰ , 2⁰
• 1.Dark ground illumination (DGI)
• 2. fluorescent antibody technique
• 3. silver impregnation techniques
• 4. PCR

45. SEROLOGIC TESTS
• Nonspecific treponemal tests: reaginic
antibodies IgM and IgG immunoglobulins -
cardiolipin-lecithin-cholesterol complex
• Venereal Disease Research Laboratory (VDRL)
- CSF - neurosyphilis
• Rapid Plasma Reagin (RPR) test

46. • Specific treponemal tests : antibodies against the
treponema
• i) Fluorescent treponemal antibody-absorbed (FTA-
ABS) test
• ii) Agglutinin assays e.g. microhaemagglutination assay
for T. pallidum (MHA-TP) sensitive.
• iii) T. pallidum passive haemagglutination (TPHA) test

48. TREATMENT
• Benzyl Penicillin
• Allergic to penicillin – erythromycin, doxycycline
• Pregnancy - desensitized - penicillin
• Crystalline penicillin – neurosyphilis – even in
patients allergic to penicillin
• Jarisch- Herxheimer phenomenon

50. 33-6

51. COMPREHENSION QUESTIONS
1. An 80-year-old man who is thought to have senile dementia dies in
a nursing home. Over the last several years, he developed ataxia and
partial paresis. An autopsy reveals severe atherosclerosis (“tree
barking”) of the ascending aorta with aneurysm formation and a small
liver with deep fibrous scars. Microscopically, there is a mononuclear
inflammatory cell infiltrate with numerous plasma cells surrounding
and within the walls of small blood vessels in most organs.
◆ What is the most likely diagnosis?
◆ What is the mechanism of this condition?
◆ What other tests could be done to confirm the diagnosis?

52. 2. Which of the following clinical signs or symptoms, if present, is most
suggestive of a diagnosis of neurosyphilis?
A. Argyll Robertson pupils B. Bitemporal hemianopia C. Hutchinson incisor
D. Perifollicular hemorrhages E. Retrobulbar palsy
3. A 24-year-old woman presents with an “inability to urinate.” She also has
pain in the vulva area and physical examination finds multiple small blisters in
this area, which consist of clear vesicles on a red base. Microscopic
examination of a smear made from one these vesicles reveals scattered
multinucleated giant cells with ground-glass nuclei. Infection with which of
the following organisms is the most likely the cause of these changes?
A. Chlamydia trachomatis B. Treponema pallidum C. Haemophilus ducreyi
D. Herpes simplex virus E. Neisseria gonorrhoeae F. Trichomonas vaginalis
4. Which of the following pathologic abnormalities is most characteristic
of tertiary syphilis?
A. Apoptosis B. Gumma C. Karyorrhexis D. Pannus E. Tophus

53. T
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