17 - chinese letter pattern hyperpigmentation

q: chinese letter pattern of hyperpigmentation is seen in ?

a. minocycline toxicity
b. bleomycin side effect
c. incontinentia pigmentosa
d. acanthosis nigricans

answer : c . this is seen in the vesicular stage of the disease .this is otherwise called bloch sulzberger or bloch siemens syndrome .

Incontinentia pigmenti is also referred to as ‘Bloch-Sulzberger syndrome’, ‘Bloch-Siemens syndrome’, ‘melanoblastosis cutis linearis’, and ‘pigmented dermatosis-Siemens-Bloch type’.

What is incontinentia pigmenti?

Incontinentia pigmenti is a rare genetic condition characterised by skin, eye, teeth and central nervous system (CNS) abnormalities. The characteristic skin lesions of incontinentia pigmenti are present at birth or develop in the first few weeks of life in approximately 90% of patients.

What causes incontinentia pigmenti?

Incontinentia pigmenti is a dominant X-linked disease. This means that the abnormal incontinentia pigmenti gene is located on one of the X chromosomes, which determine the sex of a child (XY=male; XX=female). Dominant X-linked disease means that a female with only one copy of the abnormal gene will show the disease, even though they have a normal gene on their other X-chromosome. Males who inherit the abnormal gene do not survive, resulting in miscarriage or stillbirth (X-linked dominant, male lethal syndrome). Rarely incontinentia pigmenti is reported in males with Klinefelter syndrome (XXY syndrome) or as a result of spontaneous mutations.

The incontinentia pigmenti gene is localised on chromosome Xq28. This gene normally codes for the nuclear factor-KB essential modulator protein (the NEMO or NF-kappaB gene).

What are the cutaneous features of incontinentia pigmenti?

Progressive skin rashes are the main clinical feature of the disease. There are four recognised clinical stages but their sequence is irregular, their duration variable and they may overlap.

Stage 1: Vesicular	Most often affects extremities and scalp but can arise on any part of body Red, blister-like lesions Often appear grouped in lines along the arms and legs (following so-called lines of Blaschko) Present at birth or within the first 2 weeks of life in 90% of patients May last from a few weeks to a few months and recur throughout the first few months of life chinese letter pattern of hyperpigmentation
Stage 2: Verrucous	Wart-like or pustular lesions Thick crusts or scabs form over healing blisters Lesions may be darker in skin colour (hyperpigmentation) May be present at birth but in 70-80% of patients evolves after the first stage May last for months, but rarely longer than a year
Stage 3: Hyperpigmented	Skin is darkened in a swirled pattern Pigmentation ranges from blue-grey or slate to brown Present at birth in 5-10% of patients but usually appears within the first few months of life in 90-98% of patients Darkened patches may or may not be related to areas affected in stage 1 and 2 Heavy pigmentation tends to fade slowly with increasing age
Stage 4: Atrophic/ hypopigmented	Scar-like lesions develop during adolescence and persist into adulthood Occur in 30-75% of patients Appear as pale, hairless patches or streaks

Other organ involvement

Other organs may be affected in various ways in patients with incontinentia pigmenti. These manifestations may not be seen or recognised until infancy or early childhood.

Teeth	Abnormalities in more than 80% of patients Delay in eruption of teeth (both baby and adult teeth affected) Some teeth may be missing altogether Teeth may be unusually shaped, typically pegged or cone-shaped
Nails	May be involved in up to 40% of patients Nails may be ridged, pitted, thickened or completely disfigured Usually all or multiple finger and toe nails are affected
Hair	Minor hair abnormalities in up to 50% of patients Loss or lack of hair on the crown of the head Absence of eyebrows and eyelashes Hair may be coarse, wiry and lack lustre
Eyes	Eye defects occur in 20-35% of patients Typically occur before age 5 Disease causes an abnormality in the growth of blood vessels in the inside of the eye resulting in scarring Can cause blindness but may be treated if recognised early enough
Central Nervous System	Neurological complications may occur in up to 30% of patients Most common complication is seizures which usually develop within the first few weeks of life Other manifestations include slow motor development, mental retardation, spastic paralysis, cerebral atrophy

What is the treatment for incontinentia pigmenti?

There is no specific treatment for incontinentia pigmenti. The main goal is to prevent secondary bacterial infection of skin lesions and to monitor closely the development of related problems. This should include regular dental care and close monitoring by an ophthalmologist for the first few years of life.

16 - incontinentia pigmentosa

Incontinentia Pigmenti (IP) is a genetic disorder that affects the skin, hair, teeth, and nails. It is also known as Bloch Sulzberger syndrome, Bloch Siemens syndrome, melanoblastosis cutis and naevus pigmentosus systematicus.

This disorder was first reported by Bruno Bloch, a German dermatologist in 1926 and Marion Sulzberger, an American dermatologist in 1928.

The skin lesions evolve through characteristic stages:

1. blistering (from birth to about four months of age),
2. a wart-like rash (for several months),
3. swirling macular hyperpigmentation (from about six months of age into adulthood), followed by
4. linear hypopigmentation.

chinese letter pattern of hyperpigmentation seen in incontinentia pigmentosa

Alopecia, hypodontia, abnormal tooth shape, and dystrophic nails are observed. Some patients have retinal vascular abnormalities predisposing to retinal detachment in early childhood. Cognitive delays/mental retardation are occasionally seen.

The diagnosis of IP is established by clinical findings and occasionally by corroborative skin biopsy. Molecular genetic testing of the IKBKG gene (chromosomal locus Xq28) reveals disease-causing mutations in about 80% of probands. Such testing is available clinically. In addition, females with IP have skewed X-chromosome inactivation; testing for this can be used to support the diagnosis.

IP is inherited in an X-linked dominant manner. IP is lethal in most, but not all, males. A female with IP may have inherited the IKBKG mutation from either parent or have a new gene mutation. Parents may either be clinically affected or have germline mosaicism. Affected women have a 50% risk of transmitting the mutant IKBKG allele at conception; however, most affected male conceptuses miscarry. Thus, the expected ratio for liveborn children is 33% unaffected females, 33% affected females, and 33% unaffected males. Genetic counseling, prenatal testing, and preimplantation genetic diagnosis is available.

In females, the cells expressing the mutated IKBKG gene due to lyonization selectively die around the time of birth so the X-inactivation is extremely skewed.