Complement Deficiencies AND Recurrent Infections — Written Clinical Reasoning · Phys Written Answers

Prompt

DCE-style written reasoning for Complement Deficiencies AND Recurrent Infections.

SAQ 1 — Integrated plan (12 marks)

Prompt: Provide a prioritised problem list and management sequence for this presentation. [1] [2]

Model Answer

1. Frame and red flags (3 marks) [1]

State the working diagnosis/syndrome, acuity, and what would force emergency treatment now. [1] [2]

2. Discriminating assessment (3 marks) [2]

List the key history, examination and investigations that separate dangerous differentials from benign mimics. [1] [2]

3. Treatment sequence (4 marks) [1] [3]

Immediate stabilisation, disease-specific therapy, monitoring, and complications prevention. [1] [2] [3]

4. Follow-up and communication (2 marks) [2]

Disposition, safety-net advice, and who owns follow-up. [1] [2]

SAQ 2 — Exam trap defence (8 marks)

Prompt: Name two high-yield traps in Complement Deficiencies AND Recurrent Infections and how you avoid them. [1] [2]

Model Answer

Trap one: delayed escalation of a high-risk feature — avoid by explicit red-flag checklist. [1]

Trap two: therapy mismatched to mechanism — avoid by confirming the discriminating test before escalating treatment. [2] [3]

References

[1]Mottaghipisheh H, Jahromi AM, Mirzaei F, Meri S, et al. Homozygous C1qA Deficiency Presenting as Early-Onset Systemic Lupus Erythematosus: A Case Report With a Literature Review Case Reports Immunol, 2026.PMID 42147803
[2]Consolini R, Maestrini G, Abu-Rumeileh S, Costagliola G The Intertwining Between Arthritis and Inborn Errors of Immunity J Clin Med, 2026.PMID 42123030
[3]Boccon-Gibod I, Fain O, Gobert D, Debord S, et al. French protocol for the diagnosis and management of hereditary angioedema Rev Med Interne, 2025.PMID 41168057
[4]Schejbel L, Fadnes D, Permin H, Lappegård KT, et al. Primary complement C5 deficiencies - molecular characterization and clinical review of two families Immunobiology, 2013.PMID 23743184
[5]Xi Y, Yao T, Zhang C, Zhuang T Effectiveness of safety care and clinical nursing pathway in patients undergoing cardiovascular intervention: a randomized controlled trial Perioper Med (Lond), 2026.PMID 42469924
[6]Marks FJ, Walters SJ, Sutton L, Jacques RM What statistical methods are more appropriate for predicting recruitment at the design stage of a randomised controlled trial? Trials, 2026.PMID 42469922
[7]Hajiaqaei M, Mohammadi A Transcranial random noise stimulation (tRNS) over the left dorsolateral prefrontal cortex ameliorates emotion dysregulation and executive function: a single-blind, randomized, sham-controlled clinical trial BMC Psychol, 2026.PMID 42469906
[8]Donadoni M, La Cava L, Bizzi E, Popescu Janu V, et al. Hereditary Angioedema Prophylaxis Therapy: Berotralstat and Lanadelumab Safety Profile Medicina (Kaunas), 2025.PMID 41303734

SAQ 1 — Integrated plan (12 marks)

Prompt: Provide a prioritised problem list and management sequence for this presentation. [1] [2]

Model Answer

1. Frame and red flags (3 marks) [1]

State the working diagnosis/syndrome, acuity, and what would force emergency treatment now. [1] [2]

2. Discriminating assessment (3 marks) [2]

List the key history, examination and investigations that separate dangerous differentials from benign mimics. [1] [2]

3. Treatment sequence (4 marks) [1] [3]

Immediate stabilisation, disease-specific therapy, monitoring, and complications prevention. [1] [2] [3]

4. Follow-up and communication (2 marks) [2]

Disposition, safety-net advice, and who owns follow-up. [1] [2]

SAQ 2 — Exam trap defence (8 marks)

Prompt: Name two high-yield traps in Complement Deficiencies AND Recurrent Infections and how you avoid them. [1] [2]

Model Answer

Trap one: delayed escalation of a high-risk feature — avoid by explicit red-flag checklist. [1]

Trap two: therapy mismatched to mechanism — avoid by confirming the discriminating test before escalating treatment. [2] [3]

References

[1]Mottaghipisheh H, Jahromi AM, Mirzaei F, Meri S, et al. Homozygous C1qA Deficiency Presenting as Early-Onset Systemic Lupus Erythematosus: A Case Report With a Literature Review Case Reports Immunol, 2026.PMID 42147803
[2]Consolini R, Maestrini G, Abu-Rumeileh S, Costagliola G The Intertwining Between Arthritis and Inborn Errors of Immunity J Clin Med, 2026.PMID 42123030
[3]Boccon-Gibod I, Fain O, Gobert D, Debord S, et al. French protocol for the diagnosis and management of hereditary angioedema Rev Med Interne, 2025.PMID 41168057
[4]Schejbel L, Fadnes D, Permin H, Lappegård KT, et al. Primary complement C5 deficiencies - molecular characterization and clinical review of two families Immunobiology, 2013.PMID 23743184
[5]Xi Y, Yao T, Zhang C, Zhuang T Effectiveness of safety care and clinical nursing pathway in patients undergoing cardiovascular intervention: a randomized controlled trial Perioper Med (Lond), 2026.PMID 42469924
[6]Marks FJ, Walters SJ, Sutton L, Jacques RM What statistical methods are more appropriate for predicting recruitment at the design stage of a randomised controlled trial? Trials, 2026.PMID 42469922
[7]Hajiaqaei M, Mohammadi A Transcranial random noise stimulation (tRNS) over the left dorsolateral prefrontal cortex ameliorates emotion dysregulation and executive function: a single-blind, randomized, sham-controlled clinical trial BMC Psychol, 2026.PMID 42469906
[8]Donadoni M, La Cava L, Bizzi E, Popescu Janu V, et al. Hereditary Angioedema Prophylaxis Therapy: Berotralstat and Lanadelumab Safety Profile Medicina (Kaunas), 2025.PMID 41303734