After the child is settled in the new home, pediatricians should encourage adoptive parents to seek a comprehensive assessment of the child’s health and development. The unique medical and developmental needs of internationally adopted children have led to the creation of specialty clinics throughout the USA. A significant number of internationally adopted children have acute or chronic medical problems, including growth deficiencies, anemia, elevated blood lead, dental decay, strabismus, birth defects, developmental delay, feeding and sensory difficulty, and social-emotional concerns (Chapter 34.1). All children with symptoms of an acute illness should receive immediate medical care. The American Academy of Pediatrics recommends that all children who are adopted from other countries undergo routine screening for infectious diseases and disorders of growth, development, vision, and hearing (Tables 34-1 and 34-2). Additional tests (e.g., malaria) should be ordered depending on the prevalence of disease in the child’s country of origin. If the child’s PPD is negative, a repeat skin test should be performed in 4-6 mo, since children may have false negative tests due to poor nutrition. A positive PPD should be followed by a QuantiFERON-TB Gold test to determine if the response is the result of prior BCG vaccination (Chapter 207). If they have not received hepatitis A vaccine prior to leaving the USA, parents and other household contacts (siblings, grandparents, etc.) should also be immunized. In 1 survey, 65% of internationally adopted children had no written records of overseas immunizations; however, those with records appeared to have valid records, although doses were not necessarily acceptable according to the U.S. schedule (Chapter 165).

Table 34-1 RECOMMENDED SCREENING TESTS FOR NEWLY ARRIVING ADOPTEES

Screening tests

• Complete blood cell count

• Hemoglobin identification

• Blood lead level

• Urinalysis

• Newborn screening (children <12 mo)

• Vision and hearing screening

• Developmental testing

Other screening tests to consider based on clinical findings and age of the child

• Detection of Helicobacter pylori antibody or ¹³C-urea breath test

• Stool cultures for bacterial pathogens

• Glucose-6-phosphate dehydrogenase deficiency screening

• Sickle cell

• Urine pregnancy test

Infectious disease screening (see Table 34-2)

Table 34-2 SCREENING TESTS FOR INFECTIOUS DISEASES IN IMMIGRANT CHILDREN

RECOMMENDED TESTS

Hepatitis B virus serologic testing *

• Hepatitis B surface antigen (HBsAg)

• Antibody to hepatitis B surface antigen (anti-HBs)

Hepatitis C virus serologic testing *^†

Hepatitis A virus serologic testing ^†

Varicella virus serologic testing ^†

Syphilis serologic testing

• Nontreponemal test (RPR, VDRL, or ART)

• Treponemal test (MHA-TP or FTA-ABS)

Human immunodeficiency virus 1 and 2 testing (ELISA if >18 mo, PCR if <18 mo)*

Complete blood cell count with red blood cell indices and differential (if eosinophilia, see text)

Stool examination for ova and parasites (2-3 specimens)^†

Stool examination for Giardia lamblia and Cryptosporidium antigen (1 specimen)^†

Tuberculin skin test (with CXR if >5 mm induration)*^†

OPTIONAL TESTS (FOR SPECIAL POPULATIONS OR CIRCUMSTANCES)

GC/Chlamydia

Malaria thick and thin smears

Urine for O&P for schistosomiasis, if hematuria present

ART, automated reagin test; FTA-ABS, fluorescent treponemal antibody absorption; MHA-TP, microhemagglutination test for Treponema pallidum; RPR, rapid plasma reagin; VDRL, Venereal Disease Research Laboratories.

* Repeat 3-6 mo after arrival.

^† See text.

34.1 Medical Evaluation of Immigrant (Foreign-Born) Children for Infectious Diseases

Stacene R. Maroushek

Annually, more than 210,000 foreign-born children (≤16 yr old) enter the USA as asylees, refugees, and immigrants including international adoptees. This does not include undocumented children living and working in the USA, the U.S.-born children of foreign-born parents, or the ∼2.7 million nonimmigrant visitors ≤16 yr old that legally enter the USA annually with temporary visas. It is estimated that 20% of children living in the USA are either immigrants or members of an immigrant family. With the exception of internationally adopted children, pediatric guidelines for screening these newly arrived children are sparse. The diverse countries of origin and patterns of infectious disease, the possibility of previous high-risk living circumstances (e.g., refugee camps, orphanages, foster care, rural/urban poor), the limited availability of reliable health care in many economically developing countries, the generally unknown past medical histories, and interactions with parents that may have limited English proficiency, varied educational, or economic experiences, make the medical evaluation of immigrant children a challenging but important task.

Before admission to the USA, all immigrant children are required to have a medical examination performed by a physician designated by the U.S. Department of State in their country of origin. This examination is limited to completing legal requirements for screening for certain communicable diseases and examination for serious physical or mental defects that would prevent the issue of a permanent residency visa. This evaluation is not a comprehensive assessment of the child’s health and, except in limited circumstances, laboratory or radiographic screening for infectious diseases is not required for children <15 yr old. After entry into the USA, health screenings of refugees, but not other immigrants, are recommended to be done by the resettlement state. These postarrival assessments are not legally required, and there is little tracking of refugees as they move to different cities or states. Thus, many foreign-born children have had minimal prearrival or postarrival screening for infectious diseases or other health issues.

Immunization requirements and records are also varied depending on entry status. Internationally adopted children who are younger than 10 yr are exempt from Immigration and Nationality Act (INA) regulations pertaining to immunization of immigrants before arrival in the USA. Adoptive parents are required to sign a waiver indicating their intention to comply with U.S.-recommended immunizations, whereas other immigrants need only show evidence of up-to-date, not necessarily complete, immunizations before application for permanent resident (green card) status after arrival in the USA.

Immigrants having arrived in the USA years to decades ago likely have had more limited screening than those recently arrived immigrants. If adequate records of previous screenings cannot be obtained, full to limited re-screen, especially in an ill or failing to thrive child or youth should be considered.

Infectious diseases are among the most common medical diagnoses identified in immigrant children after arrival in the USA. Children may be asymptomatic; therefore, diagnoses must be made by screening tests in addition to history and physical examination. Because of inconsistent perinatal screening for hepatitis B and hepatitis C viruses, syphilis, and HIV and the high prevalence of certain intestinal parasites and tuberculosis, all foreign-born children should be screened for these infections on arrival in the USA. Suggested screening tests for infectious diseases are listed in Table 34-2. In addition to these infections, other medical and developmental issues, including hearing, vision, dental, and mental health assessments; evaluation of growth and development; nutritional assessment; lead exposure risk; complete blood cell count with red blood cell indices; microscopic urinalysis; newborn screening (this could be done in non-neonates, too) and/or measurement of thyroid-stimulating hormone concentration; and examination for congenital anomalies (including fetal alcohol syndrome) should be considered as part of the initial evaluation of any immigrant child.

Children should be examined within 1 mo of arrival in the USA or earlier if there are immediate health concerns, but foreign-born parents may not access the health care system with their children unless prompted by illness, school vaccination, or other legal requirements. Thus, it is important to assess the completeness of previous medical screenings at any first visit with a foreign-born child.

Commonly Encountered Infections

Hepatitis B (Chapter 350)

The prevalence of hepatitis B surface antigen (HBsAg) in international adoptees and refugee children ranges from 1-5% and 4-14%, respectively, depending on the country of origin, age, and year studied. Prevalence of markers of past hepatitis B virus (HBV) infection is higher. Hepatitis B virus infection is most prevalent in immigrants from Asia, Africa, and some countries in Central and Eastern Europe and former Soviet Union (e.g., Bulgaria, Romania, Russia, and Ukraine) but also occurs in immigrants born in other countries. All immigrant children, even if previously vaccinated, coming from high-risk countries (HBsAg seropositivity >2%) should undergo serologic testing for HBV infection, including both HBsAg and antibody to HBsAg (anti-HBs), to identify current or chronic infection, past resolved infection, or evidence of previous immunization. Because HBV has a long incubation period (6 wk to 6 mo), the child may have become infected at or near the time of migration and initial testing might be falsely negative. Therefore, strong consideration should be given to a repeated evaluation 6 mo after arrival for all children, especially those from highly endemic countries. Chronic HBV infection is indicated by persistence of HBsAg for more than 6 mo. Children with HBsAg-positive test results should be evaluated to identify the presence of chronic HBV infection because chronic hepatitis B infection occurs in >90% of infants infected at birth or in the 1st year of life, and in 30% of children exposed at ages 1-5 yr. Once identified as being infected, additional testing to assess for biochemical evidence of severe or chronic liver disease or liver cancer should take place.

All exposed household or sexual contacts of a child or youth found to be HBsAg positive should be tested or have documentation of HBV immunization reviewed. Those found to be susceptible should have the series initiated. Immigrant children who test negative for HBV should receive immunization for HBV as soon as possible according to the recommended childhood and adolescent immunization schedule. Children who test positive for HBsAg are infected with HBV acutely or chronically and do not need to be immunized, but should be educated about hepatitis B disease, transmission, monitoring, and treatment.

Hepatitis A (Chapter 350)

Many immigrant children have acquired hepatitis A virus (HAV) infection early in life and are, therefore, protected. Routine serologic screening for HAV antibody generally is not indicated to detect susceptible children. However, because routine childhood immunization against HAV is recommended in the USA beginning at 1-2 yr (12-35 mo) of age, antibody testing for HAV may be considered reasonable to determine whether these children have evidence of previous infection. If a child has no evidence of previous infection, the child should be immunized against HAV as recommended.

Hepatitis C (Chapter 350)

Children from Eastern Mediterranean and Western Pacific countries, Africa, China, and Southeast Asia should be considered for hepatitis C infection screening. The decision to screen children should depend on history (e.g., receipt of blood products; traditional percutaneous procedures such as tattooing, body piercing, circumcisions, or other exposures to reused, unsterile medical devices) and the prevalence of infection in the child’s country of origin. All children coming from Egypt, which has the highest known seroprevalence (12% nationally and 40% in some villages), should be tested for hepatitis C. To distinguish chronic HCV from past/resolved HCV infection, complete testing must include serologic antibody screening (anti-HCV), followed by confirmatory HCV test (HCV RIBA or a nucleic acid test for HCV RNA).

Intestinal Pathogens

Fecal examinations for ova and parasites by an experienced laboratory will identify a pathogen in 15-35% of internationally adopted children; prevalence rates in immigrants and refugees range from 8-86%. The prevalence of intestinal parasites varies by country of origin, time period when studied, previous living conditions (including water quality, sanitation, and access to footwear) and the age of the child, with toddler/young school-aged children being most affected.

The most common pathogens identified are Giardia lamblia (Chapter 274), Trichuris trichiura (Chapter 285), Hymenolepis species (Chapter 294), Entamoeba histolytica/dispar (Chapter 273), Schistosoma species (Chapter 292), Strongyloides stercoralis (Chapter 287), Ascaris lumbricoides (Chapter 283), and hookworm (Chapter 284). All nonpregnant refugees over 2 yr of age coming from sub-Saharan Africa and Southeast Asia should be presumptively treated with predeparture albendazole. Rates of intestinal helminth infections susceptible to albendazole (Ascaris, Trichuris, or hookworm) from these areas have decreased. Nonrefugee immigrants do not receive predeparture treatment.

If documented predeparture treatment was given, an eosinophil count should be performed. An absolute eosinophil count of >400 cells/µL, if persistently elevated for 3-6 mo after arrival, should prompt further investigation for tissue-invasive parasites such as Strongyloides and Schistosoma species. If no documented predeparture treatment was given, 2 stool ova and parasite specimens obtained from separate morning stools should be examined by the concentration method, and an eosinophil count should be performed. If the child is symptomatic, including evidence of poor physical growth, but no eosinophilia is present, a single stool specimen should also be sent for G. lamblia and Cryptosporidium parvum antigen detection. All potentially pathogenic parasites found should be treated appropriately.

Therapy for intestinal parasites will be successful, but complete eradication may not occur always. Therefore, repeat ova and parasite testing after treatment in children who remain symptomatic is important to ensure successful elimination of all parasites. A follow-up eosinophil count is also recommended 3-6 mo later, and if still elevated, further evaluation is warranted. In addition, testing stool specimens for Salmonella species (Chapter 190), Shigella species (Chapter 191), Campylobacter species (Chapter 194), and Escherichia coli O157:H7 (Chapter 192) should be considered in children with diarrhea, especially if stools are bloody.

Tuberculosis (Chapter 207)

Tuberculosis (TB) commonly is encountered in immigrants from all countries because Mycobacterium tuberculosis infects ∼30% of the world’s population. Latent tuberculosis infection rates range from 0.6-30% in adoptees and up to 60% in some refugee children from North Africa and the Middle East. Prior to 2007, chest radiographs or tuberculin skin tests (TST) were generally not administered in children less than 15 yr of age and reports indicate that 1-2% of these unscreened children may enter the USA with undiagnosed active TB disease.

Since 2007, TB Technical Instructions for Medical Evaluation of Aliens have required that children aged 2-14 yr undergo a TB skin test if they are medically screened in countries where the TB rate is 20 cases or more per 100,000 population. If the skin test is positive, a chest x-ray is required. If the chest x-ray suggests TB, cultures and three sputum smears are required, all before arrival in the USA. This requirement is being phased in over a number of years, and some countries with a case rate of 20 per 100,000 may not currently be screening children. Check with the Centers for Disease Control and Prevention, Division of Global Migration and Quarantine for latest information (www.cdc.gov/ncidod/dq/technica.htm).

Because active tuberculosis disease may be more severe in young children, and latent TB infection may reactivate in later years, screening with the TST is highly important in this high-risk population. Serologic-based interferon gamma release assays such as QuantiFERON-TB Gold or T-SPOT. TB tests, although being used more frequently in adults, have not been extensively studied in children. Several studies indicate they may be unreliable in toddlers and infants.

Routine chest radiography is not indicated in asymptomatic children with negative TST results. However, some immigrants may be anergic because of malnutrition or underlying HIV infection. If malnutrition is suspected, the TST should be repeated once the child is better nourished. Receipt of bacille Calmette-Guérin (BCG) vaccine is not a contraindication to a TST, and a positive TST result should not routinely be attributed to BCG vaccine. In these children, further investigation is necessary to determine whether latent tuberculosis infection or active disease is present and therapy is needed. Empirical therapy should be considered for any child younger than 4 yr with a known recent exposure to sputum positive TB disease. Some experts repeat TST 3-6 mo after a child has left an area with high prevalence of tuberculosis. When tuberculosis is suspected in an immigrant child, serious efforts to isolate and test the organism for drug susceptibilities are imperative because of the high prevalence of drug resistance in many countries.

Syphilis (Chapter 210)

Congenital syphilis, especially with involvement of the central nervous system, may not have been diagnosed or may have been treated inadequately in immigrants from some developing countries. Each immigrant child should be screened for syphilis by reliable nontreponemal and treponemal serologic tests, regardless of history or a report of treatment. Children with positive treponemal serologic test results should be evaluated by an individual with special expertise to assess the differential diagnosis of pinta, yaws, syphilis, or other noninfectious causes of false-positive tests, and to determine the extent of the infection so appropriate treatment can be administered.

HIV Infection (Chapter 268)

The risk of HIV infection in immigrant children depends on the country of origin and individual risk factors. Because of the rapidly changing epidemiology of HIV infection, because immigrants may come from populations at high risk of infection, and because those less than 15 yr of age are not required to be tested prior to arrival, screening for HIV should be performed on all immigrant children. Although many adoptee children will have HIV test results documented in their referral information, test results from the child’s country of origin may not be reliable. Conversely, refugee testing, if performed on children, is generally done in a highly regulated International Organization for Migration laboratory. Transplacentally acquired maternal antibody in the absence of infection can be detected in a child younger than 18 mo, thus HIV antibody tests should only be used in children >18 mo of age. PCR tests for HIV RNA or DNA should be used in those less than 18 mo old. Positive HIV antibody or PCR test results in any child or youth requires immediate clinical and laboratory evaluation as well as specialist counseling.

Other Infectious Diseases

Skin infections that occur commonly in immigrant children include bacterial (e.g., impetigo), fungal (e.g., candidiasis, tinea), and ectoparasitic (e.g., scabies, pediculosis) infections. Diseases such as typhoid fever, malaria, leprosy, or melioidosis are encountered sporadically in immigrant children. Although routine screening for these diseases is not recommended, findings of fever, splenomegaly, respiratory tract infection, anemia, or eosinophilia should prompt an appropriate evaluation on the basis of the epidemiology of infectious diseases that occur in the child’s country of origin. If the child arrived within the previous year from a country where malaria is endemic, malaria should be considered in the differential diagnosis of any febrile illness, especially if no predeparture antimalarial treatment was given.

In the USA, multiple outbreaks of measles have been reported in immigrant children, including those adopted from China, and in their U.S. contacts. Prospective parents traveling internationally to adopt children, as well as their household contacts, should ensure that they have a history of natural disease or have been adequately immunized for measles according to U.S. guidelines. All people born after 1957 should receive 2 doses of measles-containing vaccine in the absence of documented measles infection or contraindication to the vaccine. Susceptible immigrant children and their families should be immunized as soon as possible after arrival according to recommended childhood, adolescent, and adult immunization schedules (Chapter 238).

Clinicians should be aware of potential diseases in high-risk immigrant children and their clinical manifestations. Some diseases, such as central nervous system cysticercosis, may have incubation periods as long as several years, and thus may not be detected during initial screening. On the basis of findings at the initial evaluation, consideration should be given to a repeat evaluation 6 mo after arrival. In most cases, the longer the interval from arrival to development of a clinical syndrome, the less likely the syndrome can be attributed to a pathogen acquired in the country of origin.

Immunizations

Some immigrants will have written documentation of immunizations received in their birth or home country. Although immunizations such as BCG, diphtheria and tetanus toxoids, and pertussis (DTP), poliovirus, measles, and hepatitis B virus vaccines often are documented, other immunizations, such as Haemophilus influenzae type b, mumps, and rubella vaccines, are given less frequently; and Streptococcus pneumoniae, human papillomavirus, meningococcal, and varicella vaccines are given rarely. Immigrant children and adolescents should receive immunizations according to the recommended schedules in the USA for healthy children and adolescents (Chapter 165). Although some vaccines with inadequate potency are used in other countries, most vaccines available worldwide are produced with adequate quality control standards and are reliable. Written documentation of immunizations can usually be accepted as evidence of adequacy of previous immunization if the vaccines, dates of administration, number of doses, intervals between doses, and age of the child at the time of immunization are consistent internally and comparable to current U.S. or World Health Organization schedules. Given the limited data available regarding verification of immunization records from other countries, measurements of serum antibodies to vaccine antigens is an option to ensure that vaccines were given and were immunogenic. An equally acceptable alternative when doubt exists is to reimmunize the child. Because the rate of more serious local reactions after diphtheria and tetanus toxoids and acellular pertussis (DTaP) vaccine increases with the number of doses administered, serologic testing for antibody to tetanus and diphtheria toxins before reimmunizing or if a serious reaction occurs can decrease risk.

In children older than 6 mo with or without written documentation of immunization, testing for antibodies to diphtheria and tetanus toxoids and poliovirus may be considered to determine whether the child has protective antibody concentrations. If the child has protective concentrations, then the immunization series should be completed as appropriate for that child’s age. In children older than 12 mo, measles, mumps, rubella, and varicella antibody concentrations may be measured to determine whether the child is immune; these antibody tests should not be performed in children younger than 12 mo because of the potential presence of maternal antibody. Many immigrant children will need a dose of mumps and rubella vaccines, because these vaccines are administered infrequently in developing countries. Measles-mumps-rubella (MMR) vaccine should be administered for mumps and rubella coverage, even if measles antibodies are present. At this time, no antibody testing is reliable or available routinely to assess immunity to pertussis. As discussed previously, serologic testing for hepatitis B should be performed for all children to determine their hepatitis B immunity status. If serologic testing is not available and receipt of immunogenic vaccines cannot be ensured, the prudent course is to provide the series.

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