Definition of Acute lymphoblastic leukemia

Acute lymphoblastic leukemia: An acute (sudden onset), rapidly progressing form of leukemia that is characterized by the presence in the blood and bone marrow of large numbers of unusually immature white blood cells destined to become lymphocytes. Acute lymphoblastic leukemia is also called acute lymphocytic leukemia and is abbreviated ALL (spoken not as the word "all", but as the three letters A-L-L). ALL is the most common cancer occurring in children, representing almost 25% of cancer among children. There is a sharp peak in the incidence of ALL incidence among children ages 2 to 3. This peak is approximately fourfold greater than that for infants and is nearly 10-fold greater than that for youths who are 19 years old.

For unexplained reasons, the incidence of ALL is substantially higher for white children than for black children, with a nearly threefold higher incidence at 2 to 3 years of age for white children compared to black children. The incidence of ALL appears to be highest in Hispanic children.

Factors associated with an increased risk of ALL have been identified. The main environmental factor is radiation, namely prenatal exposure to x-rays or postnatal exposure to high doses of radiation. Children with Down syndrome (trisomy 21) also have an increased risk for both ALL and acute myeloid leukemia (AML). About two-thirds of acute leukemia in children with Down syndrome is ALL. Increased occurrence of ALL is also associated with certain genetic conditions, including neurofibromatosis, Shwachman syndrome, Bloom syndrome, and ataxia telangiectasia.

The malignant lymphoblasts from a particular ALL patient carry antigen receptors unique to that patient. There is evidence to suggest that the specific antigen receptor may be present at birth in some patients with ALL, suggesting a prenatal origin for the leukemic clone. Similarly, some patients with ALL characterized by specific chromosome translocations have been shown to have cells containing the translocation at the time of birth.

Seventy-five to 80% of children with ALL now survive at least 5 years from diagnosis with current treatments that incorporate systemic therapy (e.g., combination chemotherapy) and specific central nervous system (CNS) preventive therapy (i.e., intrathecal chemotherapy with or without cranial irradiation). Ten-year event-free survival of multiple large prospective trials conducted in different countries for children treated primarily in the 1980s is approximately 70%.

Since nearly all children with ALL achieve an initial remission, the major obstacle to cure is bone marrow and/or extramedullary (e.g., CNS, testicular) relapse. Relapse from remission can occur during therapy or after completion of treatment. While the majority of children with recurrent ALL attain a second remission, the likelihood of cure is generally poor, particularly for those with bone marrow relapse occurring while on treatment.

Achondroplasia: The most common form of short stature with disproportionately short limbs -- dwarfism with short arms and legs. Achondroplasia is caused by mutation in the fibroblast growth factor receptor-3 gene (FGFR3), which is located on chromosome 4 in chromosome band 4p16.3.
Aside from short arms and legs, the fingers are short and the
ring and middle fingers diverge giving the hand a trident (three-
pronged) appearance. There is a typically large head with prominence of the forehead (frontal bossing), underdevelopment (hypoplasia) of the midface with cheekbones that lack prominence, and a low nasal bridge with narrow nasal passages. The brain is normal and intelligence is entirely normal in achondroplasia. However, the complications of achondroplasia can impinge on the brain and the spinal cord.
Achondroplasia is inherited as an autosomal dominant trait
affecting boys and girls equally. The parents of children with
achondroplasia are more often than not normal. Most cases of
achondroplasia are due to new mutations that appear for the first
time in the affected children.
Achondroplasia can be diagnosed before birth by molecular means.
The limited number of changes in the FGF3 gene responsible for achondroplasia and the ease with which they can be detected provide the basis for a simple method for prenatal diagnosis.

Definition of Abuse, child

Abuse, child: Child abuse is a very complex and dangerous
set of problems that include child neglect and the physical,
emotional, and sexual abuse of children.
Child neglect is the most frequently reported form of child
abuse and the most lethal. This form of abuse is defined as the
failure to provide for the shelter, safety, supervision and
nutritional needs of the child. Child neglect can be physical,
educational, or emotional neglect.
Physical neglect includes refusal of or delay in seeking health
care, abandonment, expulsion from the home or refusal to allow a
runaway to return home, and inadequate supervision.
Educational neglect includes the allowance of chronic truancy,
failure to enroll a child of mandatory school age in school, and
failure to attend to a special educational need.
Emotional neglect includes such actions as marked inattention to
the child's needs for affection, refusal of or failure to provide
needed psychological care, spouse abuse in the child's presence, and
permission of drug or alcohol use by the child.
Physical abuse is the second most frequently reported form
of child abuse and is defined as physical injury inflicted upon the
child with cruel and/or malicious intent. Physical abuse can be the
result of punching, beating, kicking, biting, burning, shaking, or
otherwise harming a child. The parent or caretaker may not have
intended to hurt the child, rather the injury may have resulted from
over-discipline or physical punishment.
Emotional abuse is the third most frequently reported form
of child abuse and includes acts or omissions by the parents or other
caregivers that could cause serious behavioral, emotional, or mental
disorders. For example, the parents/caregivers may use extreme or
bizarre forms of punishment, such as confinement of a child in a dark
closet.
Emotional child abuse is also sometimes termed psychological child
abuse, verbal child abuse, or mental injury of a child.
Sexual abuse is the least frequently reported form of child
abuse and is believed to be the most under-reported type of child
maltreatment because of the secrecy or "conspiracy of silence" that
so often characterizes these cases. Sexual abuse includes fondling a
child's genitals, intercourse, incest, rape, sodomy, exhibitionism,
and commercial exploitation through prostitution or the production of
pornographic materials.
Fatal injuries from maltreatment can result from many different
acts including severe head trauma (injury), shaken baby syndrome,
trauma to the abdomen or chest, scalding, burns, drowning,
suffocation, poisoning, etc.
Factors affecting the likelihood of potential abuse and
predisposing to child abuse include:

The abuser's childhood: child abusers often were abused as
children.
The abuser's substance abuse: at least half of all child abuse
cases involve some degree of substance abuse (alcohol, drugs, etc) by
the child's parents.
Family stress: the disintegration of the nuclear family and its
inherent support systems has been held to be associated with child
abuse.
Social forces: experts debate whether a postulated reduction in
religious/moral values coupled with an increase in the depiction of
violence by the entertainment and informational media may increase
child abuse.
The child: children at higher risk for child abuse include
infants who are felt to be "overly fussy", handicapped children, and
children with chronic diseases.
Specific "trigger" events that occur just before many fatal
parental assaults on infants and young children include: an infant's
inconsolable crying, feeding difficulties, a toddler's failed toilet
training, and exaggerated parental perceptions of acts of
"disobedience" by the child.
Children can be neglected and abused by parents, other caregivers,
or society.
Child abuse should be reported, investigated and evaluated.
The treatment and prevention of child abuse include a support
group structure coupled with visiting nurse home visits to reinforce
good parenting skills and monitor the child's well-being. Children's
school programs regarding "good touch...bad touch" can provide
parents with a forum in which to role-play and learn to avoid
potentially harmful scenarios. Parents should make sure that their
child's daycare center is licensed and has an open door policy
regarding parental visitation. The best strategy is to prevent child
abuse.
Not until the 19th century were children granted the same legal
status as domesticated animals in regard to protection against
cruelty and/or neglect. In 1962 the term "battered child syndrome"
entered medicine. By 1976 all states in the United States had adopted
laws mandating the reporting of suspected instances of child
abuse.