INTRODUCTIONHoloprosencephaly (HPE) is an uncommon congenital failure of forebrain development. Although the aetiology is heterogeneous, chromosomal abnormalities or a monogenic defect are the major causes, accounting for about 40% to 50% of HPE cases. At least 7 genes have been positively implicated, including SHH, ZIC2, SIX3, TGIF, PTCH1, GLI2, and TDGF1.

CLINICAL PICTURETwelve antenatally- and 1 postnatally-diagnosed cases are presented in this study. These comprised 6 amniotic fluid, 3 chorionic villus, 2 fetal blood, 1 peripheral blood, and 1 product of conception.

OUTCOMEThe total chromosome abnormality rate was 92.3%, comprising predominantly trisomy 13 (66.7%). There was 1 case of trisomy 18, and 3 cases of structural abnormalities, including del13q, del18p, and add4q.

CONCLUSIONDespite the poor outcome of an antenatally-diagnosed HPE and the likely decision by parents to opt for a termination of pregnancy, karyotyping and/or genetic studies should be performed to determine if a specific familial genetic or chromosomal abnormality is the cause. At the very least, a detailed chromosome analysis should be carried out on the affected individual. If the result of high resolution karyotyping is normal, Fluorescence in situ hybridisation (FISH) and/or syndrome-specific testing or isolated holoprosencephaly genetic testing may be performed. This information can be useful in making a prognosis and predicting the risk of recurrence.

Adult ; Chromosome Aberrations ; Female ; Holoprosencephaly ; diagnosis ; genetics ; Humans ; Karyotyping ; Pregnancy ; Prenatal Diagnosis ; Trisomy

INTRODUCTIONHigh workload volumes in a Cytogenetics laboratory can lead to long result turn-around times (TAT). This study aimed to improve laboratory efficiency by adopting Lean Management System initiatives to increase productivity through the elimination of wastes. This study examined if the prerequisite 20-cell analysis was sufficient for a conclusive result or if additional cell workup was necessary to ascertain the presence of a previous chromosome abnormality among cases on follow-up, or when a single abnormal cell was encountered during the analysis to determine the presence of a clone.

MATERIALS AND METHODSThe karyotype results of cases that had additional workup were retrieved from among 8040 bone marrow cases of various haematological disorders performed between June 2003 and June 2008.

RESULTSOf 8040 cases analysed, 2915 cases (36.3%) had additional cell workup. Only 49 cases (1.7%) led to the establishment of a clone. The majority of these cases could have been resolved without the additional workup, especially if fluorescence in situ hybridization (FISH) or polymerase chain reaction (PCR)-based assays had been utilised.

CONCLUSIONThis study shows that the additional workup procedure is redundant. The time saved by discontinuing the workup procedure can be used to analyse other cases, leading to increased laboratory efficiency and a faster TAT without compromise to patient care. The practice of additional workup over and above the 20- cell analysis should be dispensed with as little benefit was derived for the amount of additional manpower expended. FISH or PCR-based assays should be utilised to elucidate a case further.

Adult ; Aged ; Aged, 80 and over ; Bone Marrow ; Bone Marrow Cells ; Cytogenetics ; Efficiency ; Efficiency, Organizational ; Female ; Hematologic Diseases ; diagnosis ; pathology ; Humans ; In Situ Hybridization, Fluorescence ; instrumentation ; methods ; Karyotyping ; instrumentation ; methods ; Male ; Polymerase Chain Reaction