Bacterial Skin Infections Practice Questions

Q: Innumerable, small, normoesthetic and symmetrical skin lesions are present in which type of leprosy:

Lepromatous. ***Lepromatous*** - **Lepromatous leprosy** is characterized by a high bacterial load, leading to **innumerable, symmetrical, and poorly defined skin lesions** distributed bilaterally. - In **early lepromatous disease**, lesions may be **normoesthetic** (normal sensation) or only mildly hypesthetic before significant nerve damage develops. However, as the disease progresses, sensory loss becomes more apparent due to diffuse nerve involvement. - The combination of **innumerable + symmetrical + normoesthetic** lesions is most characteristic of **early lepromatous leprosy**. *Tuberculoid* - **Tuberculoid leprosy** typically presents with **few (1-5), well-demarcated, and often asymmetric** skin lesions. - These lesions show **marked sensory loss early** (anesthetic from onset) due to intense localized immune response and nerve damage. - Does not fit the description of innumerable, normoesthetic lesions. *Borderline tuberculoid* - **Borderline tuberculoid leprosy** features a **moderate number of lesions** (more than tuberculoid but not innumerable), which are usually well-defined. - Lesions show **noticeable sensory impairment** relatively early in the disease course. - Does not present with innumerable lesions. *Borderline lepromatous* - **Borderline lepromatous leprosy** has numerous lesions with varied morphology (macules, papules, plaques). - While extensive, sensory loss is usually **more pronounced** than in pure lepromatous leprosy due to more active nerve inflammation. - The combination of normoesthetic + innumerable + symmetrical is more specific to lepromatous rather than borderline lepromatous.

Q: Not a cutaneous manifestation of TB:

Lupus pernio. ***Lupus pernio*** - **Lupus pernio** is characteristic of **sarcoidosis**, not tuberculosis. It typically presents as violaceous, indurated plaques on the face, especially the nose, cheeks, and ears. - Its presence usually indicates chronic and systemic sarcoidosis, differentiating it from tubercular skin manifestations. *Erythema nodosum* - **Erythema nodosum** can be a cutaneous manifestation of tuberculosis, often indicating an underlying immune response to the infection. - It presents as tender, red nodules, typically on the shins, reflecting a delayed hypersensitivity reaction. *Scrofuloderma* - **Scrofuloderma** is a direct cutaneous manifestation of tuberculosis, resulting from the extension of an underlying tuberculous infection (e.g., lymph nodes, bones) to the skin. - It involves painless, purplish nodules or plaques that ulcerate and discharge pus. *Lupus vulgaris* - **Lupus vulgaris** is a chronic and progressive form of cutaneous tuberculosis, characterized by reddish-brown plaques with an "apple-jelly" appearance on diascopy. - This manifestation occurs due to hematogenous or lymphatic spread of **Mycobacterium tuberculosis** to the skin in individuals with moderate immunity.

Q: Moth-eaten alopecia is seen with:

Syphilis. ***Syphilis*** - **Moth-eaten alopecia** is a characteristic but non-specific finding in **secondary syphilis**, occurring due to immune-mediated inflammation targeting hair follicles. - It presents as patchy, non-scarring hair loss, predominantly on the scalp, eyebrows, and beard area. *Cylindroma* - **Cylindroma** is a benign adnexal tumor of the skin, typically presenting as multiple fleshy nodules on the scalp and face. - It is not associated with hair loss patterns like moth-eaten alopecia; rather, large lesions can cause pressure atrophy of hair follicles leading to localized hair loss. *Fungal infection* - **Fungal infections** of the scalp, such as tinea capitis, typically cause patches of **scaling, erythema, and broken hairs**, sometimes leading to **black dot tinea**. - While they can cause patchy hair loss, the description of "moth-eaten" is not the characteristic presentation for fungal infections. *Leprosy* - **Leprosy** can cause hair loss, particularly loss of the **lateral eyebrows** (madarosis) and body hair. - This hair loss is typically due to nerve damage leading to atrophy of hair follicles or direct granulomatous infiltration, not diffuse patchy "moth-eaten" alopecia.

Q: True about LGV ?

Proctocolitis in 2nd stage. ***Proctocolitis in 2nd stage*** - **Proctocolitis** can occur during the **secondary stage** of LGV, particularly in cases involving receptive anal intercourse where the primary inoculation occurs in the rectal mucosa. - Patients present with **bloody rectal discharge, pain, tenesmus, and diarrhea** due to lymphatic spread. - While chronic proctocolitis with strictures occurs in late-stage disease, acute proctocolitis is a manifestation of the secondary stage. *Groove's sign in 3rd stage* - **Groove sign** is actually characteristic of the **second stage**, not the third stage of LGV. - It represents the depression created when enlarged inguinal lymph nodes are separated by the inguinal ligament during the acute lymphadenopathy phase. - The third stage involves chronic complications like strictures and elephantiasis, not acute groove sign. *Bubos in 1st stage* - **Bubos** (painful, swollen regional lymph nodes) are characteristic of the **second stage** of LGV, not the first. - The first stage typically features a transient, small, painless papule or ulcer that often goes unnoticed. *Bleeding ulcer in 1st stage* - The primary lesion of LGV (first stage) is usually a **small, painless papule, vesicle, or ulceration** that is typically non-bleeding. - The primary lesion is often transient and may go unnoticed before lymphadenopathy develops.

Q: Asymmetrical nerve thickening with several hypoesthetic macules on skin indicates which stage of leprosy?

Borderline tuberculoid. ***Borderline tuberculoid*** - This stage is characterized by **prominent asymmetrical nerve thickening**, which is a hallmark feature distinguishing it from other borderline forms. - Patients typically present with **several (5-10) hypoesthetic macules** with well-defined borders and **satellite lesions** around the main lesion, reflecting a strong cell-mediated immune response. *Borderline lepromatous* - Marked by **many poorly defined lesions** that are becoming more **symmetrically distributed**. - Nerve thickening is less prominent and **more symmetrical** than in BT, reflecting a weaker cell-mediated immune response. *Tuberculoid leprosy* - Characterized by **very few skin lesions (1-5)** with **complete anesthesia** (not hypoesthesia) and well-demarcated borders. - While asymmetrical nerve thickening occurs, it lacks **satellite lesions** which are characteristic of BT leprosy. *Borderline borderline leprosy* - Represents the **most unstable form** with numerous (10-30) moderately defined lesions. - Nerve involvement is present but **less prominently asymmetrical** than in BT, with symmetry intermediate between tuberculoid and lepromatous poles.

Q: The hard chancre is seen in:

Syphilis. ***Syphilis*** - The **hard chancre** is the characteristic lesion of **primary syphilis**, appearing at the site of infection. - It is typically a **painless, indurated ulcer with raised borders and a clean base**, which often heals spontaneously even without treatment. - Associated with **non-tender regional lymphadenopathy**, distinguishing it from the painful ulcers of chancroid. *Chancroid* - Chancroid is caused by *Haemophilus ducreyi* and presents with **soft, painful ulcers** (soft chancre) that bleed easily. - Unlike the hard chancre of syphilis, these lesions are multiple and often associated with **tender, suppurative lymphadenopathy**. *Granuloma inguinale* - This condition, caused by *Klebsiella granulomatis*, is characterized by **beefy-red, granulomatous lesions** that are typically painless and highly vascular. - It does not present with a chancre, but rather with progressive ulcerative lesions that can be destructive if untreated. *LGV* - **Lymphogranuloma venereum** (LGV) is caused by specific serovars of *Chlamydia trachomatis* and initially presents as a **transient, small, often unnoticed papule or ulcer**. - The most prominent feature of LGV is later development of significant **inguinal lymphadenopathy** (buboes) rather than a firm chancre.

Q: Which of the following is true regarding leprosy?

MBL recommended treatment for 12 months duration. ***MBL recommended treatment for 12 months duration*** - **Multibacillary leprosy (MBL)** requires a longer treatment regimen to effectively eradicate the higher bacterial load and prevent relapse. - The standard **WHO multidrug therapy (MDT)** for MBL involves **Rifampicin, Dapsone**, and **Clofazimine** for **12 months**. *All deformity cases are MBL* - Deformities can occur in both **Paucibacillary (PB)** and **Multibacillary (MBL)** leprosy, particularly due to **nerve damage** from inflammation or reactions. - The presence of deformity alone does not automatically classify a case as MBL; the **bacteriological index (BI)** and clinical presentation are crucial for classification. *Grenz zone is absent in Lepromatous leprosy* - The **Grenz zone** is a clear, uninvolved band of dermis separating the epidermis from the granulomatous infiltrates, and it is a characteristic histological feature often seen in **lepromatous leprosy**. - Its presence helps distinguish lepromatous leprosy from other dermal inflammatory conditions, as it indicates the spared superficial dermis. *Any positive smear 1+ is MBL* - While a positive smear indicates the presence of *Mycobacterium leprae*, the classification as **MBL** or **PB** depends on the **Bacteriological Index (BI)**. - A **BI of 2+ or more** at any site is typically used to classify a case as MBL, along with the number of skin lesions.

Q: Malignant pustules are seen in:

Anthrax. ***Anthrax*** - Cutaneous anthrax, caused by *Bacillus anthracis*, presents with a characteristic **painless ulcer with a black eschar** (malignant pustule) and surrounding edema. - This lesion evolves from a papule to a vesicle, then to a necrotic ulcer or "malignant pustule." *Pemphigus* - Pemphigus is an **autoimmune blistering disease** characterized by fragile blisters and erosions on the skin and mucous membranes. - It does not involve "malignant pustules" but rather flaccid bullae due to acantholysis. *Tularemia* - Tularemia, caused by *Francisella tularensis*, can present with an **ulceroglandular lesion** at the site of inoculation, but this is typically a single, painful ulcer with regional lymphadenopathy, not a "malignant pustule." - The ulcer is often clean-based and lacks the characteristic black eschar seen in anthrax. *Actinomycosis* - Actinomycosis is a bacterial infection caused by *Actinomyces species*, commonly presenting as **chronic, suppurative abscesses** that form sinus tracts. - The lesions are characterized by granulomas and "sulfur granules" in the pus, not "malignant pustules."

Q: What is the diagnosis of a child with a small abrasion over the face who develops fever with chills, induration, and fiery red swelling over the face extending to the ear?

Erysipelas. ***Erysipelas*** - The presentation of **fiery red swelling** with well-demarcated, raised borders, rapidly extending from a small abrasion, especially on the face and involving the ear, is classic for erysipelas. - It also includes systemic symptoms like **fever and chills** and **induration**, which are characteristic of this superficial skin infection usually caused by **Streptococcus pyogenes**. *Anthrax* - Cutaneous anthrax typically presents with a papule that develops into a **vesicle**, then a painless ulcer with a distinctive **black eschar**, which is not described here. - While it can cause fever, the characteristic skin lesion is distinct from the red, spreading swelling seen in this case. *Carbuncle* - A carbuncle is a deep infection involving multiple hair follicles, presenting as a painful, interconnected lesion with **multiple draining sinuses**. - It is typically more localized, deeper, and pus-filled than the superficial, rapidly spreading, fiery red swelling described. *Cellulitis* - Cellulitis is a deeper infection of the dermis and subcutaneous fat, presenting with redness, warmth, and tenderness, but its borders are typically **less well-demarcated** and not as raised as in erysipelas. - While it can also occur on the face and cause systemic symptoms, the description of "fiery red" and "extending to the ear" with sharp borders makes erysipelas a more precise diagnosis.

Q: 'Coral red' color on Wood's lamp is seen in

Erythrasma. ***Erythrasma*** - Erythrasma, caused by *Corynebacterium minutissimum*, produces characteristic **porphyrins** that fluoresce **coral red** under Wood's lamp. - This specific fluorescence pattern is a key diagnostic feature for distinguishing erythrasma from other intertriginous dermatoses. *Pityriasis rosea* - This condition presents with a characteristic **herald patch** followed by smaller, oval, salmon-colored lesions in a "Christmas tree" pattern, without any specific fluorescence under Wood's lamp. - Its etiology is thought to be viral, and it does not involve the bacterial production of porphyrins. *Tinea corporis* - Also known as ringworm, tinea corporis is a dermatophyte infection that typically shows **no fluorescence** or sometimes a dull green fluorescence with some species (e.g., *Microsporum canis*), but never coral red. - Diagnosis is usually made by KOH direct microscopy of skin scrapings showing **hyphae and spores**. *Tuberous sclerosis* - This is a neurocutaneous disorder characterized by **ash-leaf spots** (hypopigmented macules) that may enhance as bright white under Wood's lamp due to loss of melanin. - It does not produce a coral red fluorescence and is a genetic condition, not an infection.

Question 1

Innumerable, small, normoesthetic and symmetrical skin lesions are present in which type of leprosy:

Accepted Answer

Lepromatous

Answer

Tuberculoid

Answer

Borderline tuberculoid

Answer

Borderline lepromatous

Question 2

Not a cutaneous manifestation of TB:

Accepted Answer

Lupus pernio

Answer

Erythema nodosum

Answer

Scrofuloderma

Answer

Lupus vulgaris

Question 3

Moth-eaten alopecia is seen with:

Accepted Answer

Syphilis

Answer

Cylindroma

Answer

Fungal infection

Answer

Leprosy

Question 4

True about LGV ?

Accepted Answer

Proctocolitis in 2nd stage

Answer

Bubos in 1st stage

Answer

Groove's sign in 3rd stage

Answer

Bleeding ulcer in 1st stage

Question 5

Asymmetrical nerve thickening with several hypoesthetic macules on skin indicates which stage of leprosy?

Accepted Answer

Borderline tuberculoid

Answer

Tuberculoid leprosy

Answer

Borderline lepromatous

Answer

Borderline borderline leprosy

Question 6

The hard chancre is seen in:

Accepted Answer

Syphilis

Answer

Chancroid

Answer

Granuloma inguinale

Answer

LGV

Question 7

Which of the following is true regarding leprosy?

Accepted Answer

MBL recommended treatment for 12 months duration

Answer

All deformity cases are MBL

Answer

Grenz zone is absent in Lepromatous leprosy

Answer

Any positive smear 1+ is MBL

Question 8

Malignant pustules are seen in:

Accepted Answer

Anthrax

Answer

Pemphigus

Answer

Tularemia

Answer

Actinomycosis

Question 9

What is the diagnosis of a child with a small abrasion over the face who develops fever with chills, induration, and fiery red swelling over the face extending to the ear?

Accepted Answer

Erysipelas

Answer

Anthrax

Answer

Carbuncle

Answer

Cellulitis

Question 10

'Coral red' color on Wood's lamp is seen in

Accepted Answer

Erythrasma

Answer

Pityriasis rosea

Answer

Tinea corporis

Answer

Tuberous sclerosis

Bacterial Skin Infections — MCQs

Bacterial Skin Infections — MCQs

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