Daily Care and Your Multidisciplinary Team

Managing DNAJC21-related Shwachman-Diamond Syndrome (SDS) requires a team approach that looks far beyond blood counts. Because this condition is so rare, care is often extrapolated from classic SDS protocols, tailored to the specific symptoms present ^[1][2]. The goal of daily management is to support growth, protect the immune system, and ensure organs—especially the pancreas and liver—are functioning as well as possible ^[3][4].

Nutrition and Pancreatic Support

Some patients with DNAJC21-related disease experience exocrine pancreatic insufficiency (EPI), where the pancreas doesn’t make enough enzymes to digest fat ^[1].

• Diagnosis and Treatment: A fecal elastase level below 200 μg/g is a useful indicator of EPI, but watery stool can produce a falsely low result. Treatment decisions to start Pancreatic Enzyme Replacement Therapy (PERT) should incorporate symptoms, growth, nutritional markers, and gastroenterology specialist assessment ^[5][3]. Never start, stop, or change PERT without GI guidance. If prescribed, enzymes must be taken with meals and snacks, and enteric-coated beads should generally not be crushed.
• Micronutrient Monitoring: Patients with SDS often struggle to absorb vitamins and minerals. In studies of broader SDS cohorts, patients frequently remain deficient in Vitamin A, Vitamin E, Selenium, and Zinc despite therapy ^[6]. While these statistics are not individualized DNAJC21 risks, your care team should routinely measure fat-soluble vitamins (A, D, E, and K) and trace elements. Do not self-prescribe high-dose fat-soluble vitamins, as they can cause toxicity.

Supporting Growth and Development

Short stature and slow weight gain are common in DNAJC21-related SDS.

• Tracking Growth: Classic SDS-specific growth charts may provide helpful context, but standard WHO/CDC charts, longitudinal trajectory, and parental heights remain very important ^[7].
• Endocrine Evaluation: If growth is very slow, an endocrinologist may evaluate the patient ^[8]. Growth hormone therapy is not routine; it has mixed evidence in broader SDS cohorts, and any potential benefits must be carefully weighed against hematologic risks by joint endocrine and hematology teams, ensuring active marrow disease is excluded ^[9][10].
• Bone Health: Because there is a higher risk for osteopenia (low bone density), periodic DXA scans may be recommended based on clinical need ^[8][11].

Immune Health and Infection Prevention

While low white blood cell counts are a known part of SDS, some individuals also have “qualitative” immune issues, meaning their immune cells don’t work perfectly ^[12].

• Baseline Workup: An initial immune assessment, including immunoglobulins (antibodies) and lymphocyte subsets (specific types of T and B cells), is often performed ^[12].
• Infection Vigilance: Low B-cell counts or low IgM levels can increase the risk of skin, soft tissue, and lung infections ^[12]. While many patients do not need daily preventative antibiotics, an individualized “fever plan” and prompt treatment of infections are essential ^[12].

Long-Term Organ Surveillance

Current research highlights the need for ongoing monitoring of the liver and other systems, even if feeling well.

• Liver Health: Liver disease, including chronic hepatitis and cirrhosis, has been documented in classic SBDS-related SDS and some DNAJC21 cases ^[13][1]. Routine blood tests for liver enzymes are standard, but scheduled imaging (like ultrasounds) should be dependent on abnormal blood tests, hepatomegaly, symptoms, or specialist advice, rather than being a universal requirement ^[13].
• Multidisciplinary Team: Ideally, care should be coordinated by a “medical home” that includes a Hematologist/Oncologist, Gastroenterologist/Nutritionist, Endocrinologist, Immunologist, Geneticist, and Dentist/Ophthalmologist ^[2][1].